Database Info

to sbf before rom install or not?

im hoping to generate a consensus from this post. i see some ppl like to sbf before each new rom install and other not. is it necessary and why>?

From my understanding of the ROM development for the android platforms that still have to have proprietary frameworks, ie: Motoblur (droid2/X) and Touch Wiz (Galaxy S) you are not wiping and installing a whole new operating system like you do when you flash a HTC phone. So youre really just adding onto what you already have as a base. So it would be like taking a car and taking out stock parts and swapping for performance parts like exhaust, intake, etc.
This is just my understanding, it could be wrong. But my opinion and preference is when you change development teams like team defuse to say Jrummy16 roms, I like to SBF to stock to have a clean base. Sure its a PITA, but it keeps things from going horribly wrong.
gammaxgoblin said:
im hoping to generate a consensus from this post. i see some ppl like to sbf before each new rom install and other not. is it necessary and why>?
Click to expand...
Click to collapse

SBFing before installing a new ROM is something I would recommend. I have had slight problems such as the clock keeping the color from the ROM before it, and just minor stuff like that. I really don't think its needed but I would say if you plan on keeping the new ROM for a long amount of time it would be better to SBF first just so you know that everything is going to be okay.

I would also advice to sbf back to stock, reroot and then insstall the new custom rom you want to run.
the only reason is since the roms are all diffrent then one another and have to generall base (besides stock) then flashing (sbf) to stock is a good idea to have the rom running at the fastest most stable potential.

Why flash custom Roms?

Can a kernel be flashed without a rom and vice versa?
Does it erase all saved data to flash a kernel? A rom?
The designations KD1, KB5, KJ6, wtf do these represent?
What is firmware version 2.2.1? Does this dictate what kernels/roms will work?
My phone came stock with
Baseband version: T959VUVKD1
after an unsuccessful root, it now it has
Baseband version: T959VUVKB5
What's the difference? Is my new one better?
My kernel is now 2.6.32.9
Wasn't stock kernel 2.2.1?
Why bother switching kernels/Roms in the first place? It seems like it's just a big headache. Launcher apps seem to provide more customization then alternate Roms. What gives?
Thanks in advance, this may seem noob but I find it hard just finding BASIC information sometimes.
I've spent a LOT of time dicking around with this new phone (my first smartphone) and I love the fact that it is customizable it but it takes up too much time to have to read up on everything, flash, then re load all my icons, screw that. I just want to know what is the best, fastest, simplest, most customizable rom/kernel combo up front, or I'm going back to stock, I have to believe that they designed the stock OS around the phone to maximize effectiveness.
Thanks in advance

Alot of questions but I'll attempt to answer them. Disclaimer though, I havent been on these forums for that long so my answers may not be correct and I wont be held responsible for incorrect info.
Farlander said:
Can a kernel be flashed without a rom and vice versa?
Does it erase all saved data to flash a kernel? A rom?
Click to expand...
Click to collapse
Yes a kernel can be flashed without a rom, but roms come with kernels already on them. When flashing a kernel, data on you're device is kept, but not vice versa.
The designations KD1, KB5, KJ6, wtf do these represent?
Click to expand...
Click to collapse
They are versions. They are labeled in alphanumeric order. Example, KB5 is the oldest of the three, KD1 is newer, and KJ6 is the newest (and the newest kernel at the moment for this phone as well).
What is firmware version 2.2.1? Does this dictate what kernels/roms will work?
Click to expand...
Click to collapse
2.2.x are Froyo (Frozen Yogurt) versions. 2.3.x are Gingerbread versionss with the Gingerbread bootloaders that are needed to flash most roms on here with Clockwork Mod (CWM).
General Android Knowledge:
Cupcake < Donut < Eclair < Froyo < Gingerbread (GB) < Honeycomb < Icecream Sandwich (ICS)
My phone came stock with
Baseband version: T959VUVKD1
after an unsuccessful root, it now it has
Baseband version: T959VUVKB5
What's the difference? Is my new one better?
Click to expand...
Click to collapse
Well "better" is relative, but it is indeed older. Also, try using the new SuperOneClick to root next time if you haven't.
http://forum.xda-developers.com/showthread.php?t=803682
My kernel is now 2.6.32.9
Wasn't stock kernel 2.2.1?
Click to expand...
Click to collapse
I'm noob so idk how to answer this.
Why bother switching kernels/Roms in the first place? It seems like it's just a big headache. Launcher apps seem to provide more customization then alternate Roms. What gives?
Click to expand...
Click to collapse
Custom ROMs can add features, take away bloatware (relatively useless programs that come preloaded with the phone), and provide functional inprovements (such as KJ6's better WiFi reception.
Thanks in advance, this may seem noob but I find it hard just finding BASIC information sometimes.
I've spent a LOT of time dicking around with this new phone (my first smartphone) and I love the fact that it is customizable it but it takes up too much time to have to read up on everything, flash, then re load all my icons, screw that. I just want to know what is the best, fastest, simplest, most customizable rom/kernel combo up front, or I'm going back to stock, I have to believe that they designed the stock OS around the phone to maximize effectiveness.
Thanks in advance
Click to expand...
Click to collapse
You may just want to just follow this guide for now:
Then after which, use SuperOneClick (SOC) to root
After you get yourself situated here, then move on to bigger and better roms such as RaverX3X's Octane:
http://forum.xda-developers.com/showthread.php?t=1305145
or Somairotevoli's 2.3.6 Debloated SimplySimple:
http://forum.xda-developers.com/showthread.php?t=1321611
Be sure to always follow the OP's Instructions to the T. For example, when wiping or mounting.
And UMMU mounts means in CWM under mounts set them to:
Unmount
Mount
Mount
Unmount
Hope this helped
Oh also, if all else ever fails when attemoting to flash a ROM, try the method found here:
http://forum.xda-developers.com/showthread.php?t=1223765

Farlander said:
Can a kernel be flashed without a rom and vice versa?
Does it erase all saved data to flash a kernel? A rom?
The designations KD1, KB5, KJ6, wtf do these represent?
What is firmware version 2.2.1? Does this dictate what kernels/roms will work?
My phone came stock with
Baseband version: T959VUVKD1
after an unsuccessful root, it now it has
Baseband version: T959VUVKB5
What's the difference? Is my new one better?
My kernel is now 2.6.32.9
Wasn't stock kernel 2.2.1?
Why bother switching kernels/Roms in the first place? It seems like it's just a big headache. Launcher apps seem to provide more customization then alternate Roms. What gives?
Thanks in advance, this may seem noob but I find it hard just finding BASIC information sometimes.
I've spent a LOT of time dicking around with this new phone (my first smartphone) and I love the fact that it is customizable it but it takes up too much time to have to read up on everything, flash, then re load all my icons, screw that. I just want to know what is the best, fastest, simplest, most customizable rom/kernel combo up front, or I'm going back to stock, I have to believe that they designed the stock OS around the phone to maximize effectiveness.
Thanks in advance
Click to expand...
Click to collapse
I'll do my best to answer this; hope I don't skip anything
Can a kernel be flashed without a rom and vice versa?
- The kernel is a traffic cop. It is what controls the underlying hardware in your phone, on your tablet, or on your PC. It handles things like memory management and allocation, access to hardware, process scheduling, and much more. You can flash a kernel onto an existing ROM (for example, Gingerbread VUVKG4 ROM with a modified KG4 kernel that has root access). The kernel you flash replaces the one that's already there. When you flash a ROM, it has a kernel already in it.
Does it erase all saved data to flash a kernel? A rom?
- Generally flashing a kernel does not wipe any of your data as you're only replacing the kernel. Flashing a ROM can wipe your data; it really depends on what you're flashing. It's always good practice to make a backup before flashing unless you've nothing on the phone to lose. Flashing a ROM that does wipe your data will not wipe the contents of your sdcard, it wipes the /data and other partitions on the phone's internal memory/storage.
The designations KD1, KB5, KJ6, wtf do these represent?
- Versions. Generally ROMs for our model of phone (Galaxy S 4G, SGH-T959V) have a name like VUVKB5, VUVKD1, or VUVKJ6. The last two characters correspond to a certain build/version number. The more recent the last two characters the more recent the build. The builds for our phone were on 2.2 (Froyo) through KD1 then went to 2.3 (Gingerbread) starting with KF1. Gingerbread required updated boot loaders for the phone. Without the proper boot loaders the phone wouldn't work.
What is firmware version 2.2.1? Does this dictate what kernels/roms will work?
- 2.2.1 is Froyo. It's a version of the Android operating system (OS). It does not dictate what will work, per-se. Rather it's telling you what version of the OS your phone is currently running. If you were to try and flash something, say a kernel, you'd definitely need to know what version you are on so that you flash a kernel/ROM for that version. You can upgrade to newer ROMs, though, say to go from 2.2.1 (KD1) to 2.3.6 (KJ6). You just have to make sure you have all of the right pieces in place first.
My phone came stock with
Baseband version: T959VUVKD1
after an unsuccessful root, it now it has
Baseband version: T959VUVKB5
What's the difference? Is my new one better?
- The "new" one is actually older, which means it is missing bug/performance fixes and the like.
My kernel is now 2.6.32.9
Wasn't stock kernel 2.2.1?
- Confusing, isn't it? The 2.6.32.9 is the kernel version & 2.2.1 is the ROM version. When you upgrade ROMs there's a good chance the kernel version will change, too, but not necessarily. They are independent numbers but kernels/ROMs are dependent upon one another. Clear as mud, right?
Why bother switching kernels/Roms in the first place? It seems like it's just a big headache. Launcher apps seem to provide more customization then alternate Roms. What gives?
- It's a personal preference most of the time. You could upgrade to the latest release ROM by Samsung which is VUVKJ6 using their Kies Mini software. It's Gingerbread based, faster, better battery life, wifi is a little weaker. Just make sure you backup any information you want to keep first. I generally keep my contacts synched with T-Mobile or Google and after a data wipe they sync back to the phone.
As for flashing custom ROMs you'd have to read up on the different ones to see if they interest you. Some increase performance, some have mad themes wrapped up in them, some have better battery life, some do their best to roll all of that up into them.
In short, you don't have to flash anything. The development community here enjoys doing it though despite what headaches it might bring. It enables us to hack/tweak the phone to see what it can do, what performance we can wring out of it, etc. I've learned a lot in the little time I've been in this community and have a TON more to learn.
I've spent a LOT of time dicking around with this new phone (my first smartphone) and I love the fact that it is customizable it but it takes up too much time to have to read up on everything, flash, then re load all my icons, screw that. I just want to know what is the best, fastest, simplest, most customizable rom/kernel combo up front, or I'm going back to stock, I have to believe that they designed the stock OS around the phone to maximize effectiveness.
- Unfortunately reading up on it, trying ROMs out, and going through some trials and tribulations is a part of the process. Which is the best ROM is strictly subjective so you'd get a bunch of different answers from a bunch of different people.
The best thing I can suggest is, if you're really interested, to take the time to read the stickies in the different forums (General, Q&A, Developer, etc.). They contain a plethora of information that will actually help you to avoid a lot of the problems. Read some threads on different ROMs & issues. You'll find a lot of "I had this problem" followed by the developer or someone else saying "Yeah, I fixed that" or "here's how to avoid/fix it". Utilize the search feature; it's there to help. The more research you do on your own the more you will learn and the less likely you'll get flamed by anyone for not trying to help yourself before asking for the help of others.
Welcome to the forums. Best of luck to you.

Kudos to you both I hope other noobs find this info as well. I think I'll flash KJ6 deodexed (faster/cleaner/more customizable right?) rooted. I don't really see the need for CWM or Titanium unless there's a ton of bloatware to remove, or I want to go crazy flashing ROMS - from what I gather, with CWM you can modify the recovery mode so that new roms can be installed right from the phone?
I have really looking for some specific key features that would improve my experience, such as a customizable destination folder for camera pics, i.e. SD card, not internal memory, a good all-time gestures program, wifi file sharing w/ pc, some cool widgets and animations, and a major reduction in the spyware content and background data of the phone, specifically google apps that try to sync my entire brain.

Farlander said:
...from what I gather, with CWM you can modify the recovery mode so that new roms can be installed right from the phone?
Click to expand...
Click to collapse
Basically, but you always have to be careful when doing so. Make backups of your data and follow the instructions carefully unless you really enjoy losing important files and using Odin lol.
I have really looking for some specific key features that would improve my experience, such as a customizable destination folder for camera pics, i.e. SD card, not internal memory, a good all-time gestures program, wifi file sharing w/ pc, some cool widgets and animations, and a major reduction in the spyware content and background data of the phone, specifically google apps that try to sync my entire brain.
Click to expand...
Click to collapse
I already thought the default destination for Camera pictures was in sdcard/DCIM ? And for cool widgets and animations, you are better off using a custom Launcher, such as GO Launcher EX. A ton of roms on here, however, do offer very nice looking themes and many remove bloatware.
My advice: get comfortable with CWM and flash a few roms; however many you need until you know you're preferences.

[Q] Clean Rom

Hello everyone,
What exactly does Clean Rom do? How is it different from what comes with the phone stock? Will Clean Rom mess with the updates that are pushed to our phones? Any big differences between layout?
Sorry for all the questions. I'm just not familiar with modifying my phone.

Must read more. Spend as much time as you can reading in the dev section. Clean ROM removes all of the ATT bloat and adds functionality like the FM radio and remapping the 3 dot menu button that takes up screen real-estate to the recent apps softkey. The recent apps can be accessed by holding down the home button, like we're familiar with. It also has performance and battery tweaks (says so in the changelog, haven't been using it long enough to notice). I flashed it the day before yesterday and I'm liking it.
Sent from my HTC One X

Clean Rom doesn't use profane language, think of it as the Will Smith of Roms...
Sent from my HOX running WCX

Did you bother to go to the Development forum, and read the CleanROM threads? They very well describe the features of each version of CleanROM.
You don't ever want to install an OTA update once on a custom ROM. It won't be compatible. Either it won't install, or it will remove root, or it will totally bork the system. The devs typically keep their ROM updated to the newest firmware base, and often long before the OTAs go out. So there is virtually never a benefit to updating via OTA (even if it did work).

Most custom ROMs prevent you from even getting an update pushed in the first place. Kind of a non-issue there.
To the OP, if you want to flash custom, just do it. Spend a few days on Clean, try out Smokin's ROM, too. Just find something you like. Worst that can happen is you RUU back to stock.
Sent from my HTC One X using Tapatalk 2

SoberGuy said:
Most custom ROMs prevent you from even getting an update pushed in the first place. Kind of a non-issue there.
Click to expand...
Click to collapse
Depends on the device, and I believe the carrier (and maybe the custom ROM as you mentioned). I've gotten OTA notification, and even able to download OTA (didn't install it, just to see if it would actually download . . . some have said custom ROMs will prevent that too) on 2 previous HTC devices on custom ROMs. But one was a Canada Bell phone used on AT&T, and the other was the WiFi-only Flyer tablet. So it may be that AT&T somehow directly blocks OTA to rooted phones.

redpoint73 said:
Depends on the device, and I believe the carrier (and maybe the custom ROM as you mentioned). I've gotten OTA notification, and even able to download OTA (didn't install it, just to see if it would actually download . . . some have said custom ROMs will prevent that too) on 2 previous HTC devices on custom ROMs. But one was a Canada Bell phone used on AT&T, and the other was the WiFi-only Flyer tablet. So it may be that AT&T somehow directly blocks OTA to rooted phones.
Click to expand...
Click to collapse
I don't think att can see your on a custom ROM, it has to do with if the developer is able to include that ability or not.

Thank you for the replies!
I'm trying my best to understand how Clean Rom works. Is it the same thing as rooting a phone? Any disadvantages of using Clean Rom?
I'm just curious about how it works because I tried jailbreaking my iPhone and that made it very crash prone. It's a bad example but it's the reason why I never tried using custom software again but I'm interested in giving this a try. I only get about 2 hours screen time and about 12 hours of screen off time for my phone to die.
I did the HTC battery test and my phone went down to 92% so I'm pretty sure it's not the battery that's wrong with the phone.

RPTheLefty said:
I'm trying my best to understand how Clean Rom works. Is it the same thing as rooting a phone?
Click to expand...
Click to collapse
It appears you need to do more reading to get a better understanding or root, ROMs, etc.
Root is just a change of permissions on your phone. It allows the user and apps access to system files that are normally restricted. Nothing more, nothing less.
Clean ROM (or installation of any custom ROM) is a total replacement of the firmware or operating system of the phone (also called a "ROM"). Clean ROM in particular is mostly based on the latest stock firmware version, but cleaned up to remove bloat, optimizations to make it faster and smoother, and some cool added features. There are 3 different versions of CleanROM. Just read the threads for each version to learn the differences.
I don't really keep up with iPhone stuff. But my understanding is that jailbreaking adds functionality, but makes the system less stable.
Whether a custom ROM on Android makes the phone more or less stable depends on the ROM. Some are ported from other phones, to give new UI look or functions, but can be a bit buggy at first. But any good ROM will be stable once it reaches "maturity" and the bugs are worked out. They can be very stable, and even more stable and smoother than the stock ROM. Which is one of the points of running a custom ROM.
CleanROM in particular is based on stock firmware, just cleaned up. So its very stable. Just as stable as stock, a bit smoother in some places, and with some awesome added features. Any disadvantages? Not really. But you need to unlock the bootloader to install any custom ROM, which voids the warranty. nd flashing anything to the phone has the risk of damage if you don't follow the instructions properly. Thats the only downsides I can think of (for any custom ROM, not just for CleanROM).

Redpoint had an excellent summary.
If you're looking for battery life improvement, there are significant advantages to a custom ROM. Some will allow you to adjust the clock rate for the processors. So you can turn the up a bit (overclock) to get incredible performance, or you can turn them down a bit (underclock) to get better battery life.
If that's your main goal, I personally suggest Sick Sense from Smokingl337. He has incorporated this into his ROM, and the reports I've seen have been positive. I had used his ROM before, and I did like it. The day I flashed CleanROM due to a minor bug, Smokinl337 updated his ROM to fix that bug. Figures! But I'll be going back to Sick Sense pretty soon, I'm sure.
Hopefully you can find something that works for you.
Sent from my HTC One X using Tapatalk 2

Different kernel or different radio may also help battery life.
But you need to root, SuperCID, and unlock bootloader to do any of these things (including flashing custom ROMs). So head over to Development and start reading:
http://forum.xda-developers.com/showthread.php?t=1671237

There is also a clean rom developers edition that takes out most of the HTC sense... there is the cm9 alpha 4 rom that seems very stable...
Sent from my HTC One X using Tapatalk 2

OP, I was in your shoes last week. New to android/roms etc. I rooted, unlocked the bootloader and flashed Clean Rom. Just follow the instructions in the associated threads and you'll be fine.

custom rom and kernals, should one install them?

I recently ordered the OPO and I was wondering if there was any point to installing a rom and a kernal.
Are there any important/good/large beneficial features and stuff to installing them?
Is it recommended to install one?
I'm just trying to decide whether or not to install rom/kernal before I get the phone so when I get it, I can work on it right away.

dlwhdrlf said:
I recently ordered the OPO and I was wondering if there was any point to installing a rom and a kernal.
Are there any important/good/large beneficial features and stuff to installing them?
Is it recommended to install one?
I'm just trying to decide whether or not to install rom/kernal before I get the phone so when I get it, I can work on it right away.
Click to expand...
Click to collapse
The phone works great out of the box, although it has some bugs.
So you install custom ROMs and/or kernels if you want to get the bugs fixed (e.g. the battery drain), you have a ROM you like for other devices you had (e.g. Paranoid), or you just like the idea of flashing something every couple of weeks, when the ROM is updated...

Dzhedaj said:
The phone works great out of the box, although it has some bugs.
So you install custom ROMs and/or kernels if you want to get the bugs fixed (e.g. the battery drain), you have a ROM you like for other devices you had (e.g. Paranoid), or you just like the idea of flashing something every couple of weeks, when the ROM is updated...
Click to expand...
Click to collapse
I have to disagree with your first statement. I've had no bugs or battery drain with stock CM11s except for 30O which is now obsolete. Custom ROMs are for different feature sets and those who like to tinker

dlwhdrlf said:
I recently ordered the OPO and I was wondering if there was any point to installing a rom and a kernal.
Are there any important/good/large beneficial features and stuff to installing them?
Is it recommended to install one?
I'm just trying to decide whether or not to install rom/kernal before I get the phone so when I get it, I can work on it right away.
Click to expand...
Click to collapse
Nobody can answer this question for you. There are points to installing custom ROMs and kernels, and each user has their own reasons for doing so. Only you can decide whether CM11S is a good fit for you, if not then try custom ROMs. It all depends on what you want to get out of your phone.
Transmitted via Bacon

How to figure out what is causing heat and battery usage (CPU and Battery usage)

Hello. I have the GS5. For over three months it overheats like hell. Why because I did the firmware update and it all started with this.
TL;DR: I need an app or program that shows detailed percentage of usage and temperatures of apps. It would be great if you can find a real-time monitoring one like on PCs. My phone is rooted so feel free to recommend any app that suit my needs.
It overheats so much that I can barely able to hold the phone because it slips through so easily from my hand (nope my hands are not dirty, I wash them with lots of soaps ).
I bought a case and it is still somewhat hard to hold the phone with one hand but the case surely helped. Can use it with two hands but was able to use with one hand without any problems so why should I accept this right?
The cpu is around 40 Celsius at idle to very low usage. The battery is around 28 Celsius at idle. The room temps is 26 Celsius.
After using my phone for about fifteen mins, the battery is going up to 36-38 Celsius. The cpu is around 50 Celsius. Not playing games at all, just surfing on the web and installing one to two apps from Android Market. Do you think it is normal or excessive? I fell the heat in my hands. It was not been like this before the firmware update.
Although I did all wipes and flash the whole rom from scratch (even ticked Nand Erase All), my problem still persists so I am out of ideas. Maybe I can buy a new battery and a charger but I would like to make sure that the problem is not causing by software. Thank you.

karasahin said:
Hello. I have the GS5. For over three months it overheats like hell. Why because I did the firmware update and it all started with this.
TL;DR: I need an app or program that shows detailed percentage of usage and temperatures of apps. It would be great if you can find a real-time monitoring one like on PCs. My phone is rooted so feel free to recommend any app that suit my needs.
It overheats so much that I can barely able to hold the phone because it slips through so easily from my hand (nope my hands are not dirty, I wash them with lots of soaps ).
I bought a case and it is still somewhat hard to hold the phone with one hand but the case surely helped. Can use it with two hands but was able to use with one hand without any problems so why should I accept this right?
The cpu is around 40 Celsius at idle to very low usage. The battery is around 28 Celsius at idle. The room temps is 26 Celsius.
After using my phone for about fifteen mins, the battery is going up to 36-38 Celsius. The cpu is around 50 Celsius. Not playing games at all, just surfing on the web and installing one to two apps from Android Market. Do you think it is normal or excessive? I fell the heat in my hands. It was not been like this before the firmware update.
Although I did all wipes and flash the whole rom from scratch (even ticked Nand Erase All), my problem still persists so I am out of ideas. Maybe I can buy a new battery and a charger but I would like to make sure that the problem is not causing by software. Thank you.
Click to expand...
Click to collapse
Please provide further information in regard to your device e.g. ROM, kernel etc.

noc.jfcbs said:
Please provide further information in regard to your device e.g. ROM, kernel etc.
Click to expand...
Click to collapse
Sure. I haven't touched to kernel yet but I have a custom rom installed. I just installed it yesterday. Was using stock rom of Lollipop 5.0 of my country before. I also tried the UK rom (BTU) but all the same.

karasahin said:
Sure. I haven't touched to kernel yet but I have a custom rom installed. I just installed it yesterday. Was using stock rom of Lollipop 5.0 of my country before. I also tried the UK rom (BTU) but all the same.
Click to expand...
Click to collapse
Despite only little information available, I assume the issue is kernel related. Had you e.g. overclocked and over-voltaged? Most likely not as you were on stock.
Your custom ROM certainly came with its own, new kernel. I suggest to monitor the overheating first as you just recently flashed the custom ROM. However, you can also play with the kernel settings (my current one has its own control-apk, or by using e.g. an apk called "Kernel Adiutor") to see what's best serves your requirements. If you're not happy with the custom ROM's kernel, you can flash a custom kernel but check compatibility first. And remember, when you're on a custom kernel every time you flash the custom ROM you'll have to re-flash the kernel.
Here's a real good guide regarding CPU governors, I/O schedulers and more:
http://forum.xda-developers.com/general/general/ref-to-date-guide-cpu-governors-o-t3048957

noc.jfcbs said:
Despite only little information available, I assume the issue is kernel related. Had you e.g. overclocked and over-voltaged? Most likely not as you were on stock.
Your custom ROM certainly came with its own, new kernel. I suggest to monitor the overheating first as you just recently flashed the custom ROM. However, you can also play with the kernel settings (my current one has its own control-apk, or by using e.g. an apk called "Kernel Adiutor") to see what's best serves your requirements. If you're not happy with the custom ROM's kernel, you can flash a custom kernel but check compatibility first. And remember, when you're on a custom kernel every time you flash the custom ROM you'll have to re-flash the kernel.
Here's a real good guide regarding CPU governors, I/O schedulers and more:
http://forum.xda-developers.com/general/general/ref-to-date-guide-cpu-governors-o-t3048957
Click to expand...
Click to collapse
So I think I should update kernel on this custom rom with a new one? Because the OP says that flash hispasian kernel after flashing his rom. I haven't do that yet, nor I have experience about it. I believe I have a custom rom with stock kernel right now. I don't think it is related to custom rom. It overheats like I was on stock rom. Could be kernel. Can kernel be updated through the firmware update? It may explain why it starts to overheating after that. No, I haven't overclocked and over-voltaged the cpu. Maybe it came overclocked or over-voltaged with this custom rom but it isn't described.

karasahin said:
So I think I should update kernel on this custom rom with a new one? Because the OP says that flash hispasian kernel after flashing his rom. I haven't do that yet, nor I have experience about it. I believe I have a custom rom with stock kernel right now. I don't think it is related to custom rom. It overheats like I was on stock rom. Could be kernel. Can kernel be updated through the firmware update? It may explain why it starts to overheating after that. No, I haven't overclocked and over-voltaged the cpu. Maybe it came overclocked or over-voltaged with this custom rom but it isn't described.
Click to expand...
Click to collapse
I suggest to surf your custom ROM's thread and to figure out, which kernels can go with this ROM and which are the experiences of other users with the respective kernel.
Firmware updates (I assume you mean now updates of your ROM) won't solve your problem because with the update comes its own kernel i.e. you need to flash afterwards the kernel you want again.
I always flash my custom kernel through recovery. As recovery, I personally recommend TWRP in its latest version (as you see in my signature block, I'm using TWRP v3.0.2). An in my opinion very good tool, to install (actually flash through your current recovery) TWRP is via an App (apk) called "Flashify".
After you've flash TWRP and rebooted, google how to flash a kernel or search XDA for my postings. I think I already describe somewhere how to do so.

noc.jfcbs said:
I suggest to surf your custom ROM's thread and to figure out, which kernels can go with this ROM and which are the experiences of other users with the respective kernel.
Firmware updates (I assume you mean now updates of your ROM) won't solve your problem because with the update comes its own kernel i.e. you need to flash afterwards the kernel you want again.
I always flash my custom kernel through recovery. As recovery, I personally recommend TWRP in its latest version (as you see in my signature block, I'm using TWRP v3.0.2). An in my opinion very good tool, to install (actually flash through your current recovery) TWRP is via an App (apk) called "Flashify".
After you've flash TWRP and rebooted, google how to flash a kernel or search XDA for my postings. I think I already describe somewhere how to do so.
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Click to collapse
I mentioned firmware updates because I was wondering if stock (Samsung) rom firmware update did break something in stock kernel. Is it possible? I'm %99 positive this happened after the latest firmware update. I mainly flashed this custom rom to get rid of overheating problem but the problem persists.
I just flashed HispAsian kernel, which the creator of this custom ROM recommended, through TWRP and works fine for now. But nothing's changed about overheating.

karasahin said:
I mentioned firmware updates because I was wondering if stock (Samsung) rom firmware update did break something in stock kernel. Is it possible? I'm %99 positive this happened after the latest firmware update. I mainly flashed this custom rom to get rid of overheating problem but the problem persists.
I just flashed HispAsian kernel, which the creator of this custom ROM recommended, through TWRP and works fine for now. But nothing's changed about overheating.
Click to expand...
Click to collapse
Look into the kernel settings as mentioned in post #4 (http://forum.xda-developers.com/showpost.php?p=67135599&postcount=4).
Before you change anything I suggest to educate yourself via the thread mentioned in that post, too.

noc.jfcbs said:
Look into the kernel settings as mentioned in post #4 (http://forum.xda-developers.com/showpost.php?p=67135599&postcount=4).
Before you change anything I suggest to educate yourself via the thread mentioned in that post, too.
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Click to collapse
I actually don't care about custom roms. As long as I can find a solution for stock roms I would return to them. Could you please give me your solution for stock roms?

karasahin said:
I actually don't care about custom roms. As long as I can find a solution for stock roms I would return to them. Could you please give me your solution for stock roms?
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It's always your decision and desire. I think everything said also applies to stock ROM. Check your kernel settings and manipulate to your needs. Some tools were mentioned before.

noc.jfcbs said:
It's always your decision and desire. I think everything said also applies to stock ROM. Check your kernel settings and manipulate to your needs. Some tools were mentioned before.
Click to expand...
Click to collapse
It is too complicated for me. If you could just point how to downlock the CPU's clock speed then I can try and see if it works to prevent overheating.
Also let's say I decide to return to stock rom. Will current kernel replace with stock one?

karasahin said:
It is too complicated for me. If you could just point how to downlock the CPU's clock speed then I can try and see if it works to prevent overheating.
Also let's say I decide to return to stock rom. Will current kernel replace with stock one?
Click to expand...
Click to collapse
I'm not familiar with your phone (wasn't it a Samsung Galaxy S5) or your stock ROM (Lollipop?). I suggest that you address your questions in the GSG5 forum, where the gurus for your phone rest. Sorry for that.
Anyhow, I added two screenshots of the apk "Kernel Adiutor" (first two), and two of AGNi control, which came with my kernel. As you see both of them support manipulation of kernel settings.
IRT your last question: I'm convinced flashing stock ROM is also replacing current kernel. ...but as said: GSG5 forum.