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Successfully OCed to 1.2 ghz (80 voltage) on motorola defy. My temperature is going up to 41°c from 37°c within 10 minutes of PSX gameplay...is it safe? and how high temp goes up so that it is on the safe side. I mean is there a limit to the temperature of the CPU after that it's dangerous?
Also should the freqeuncies of Max and Min be same? what's the difference
Please i need a fast reply on this !
thanks in advance
no reply? don't tell me no one knows this?
The min and max should not be the same. Min is the lowest you want the CPU to scale down too and max is the highest frequency you want to overclock too. On my HTC Desire min is set to 245 mhz and max 1113 mhz.
I don't know about the temperature, someone else should elaborate on that.
Sent from my HTC Desire
You should be fine... These CPU's are designed to run without a fan or cooling of any kind.
I just applied dsextons 1.6ghz..tegrak overclock optimizations voltage..i was just wondering if there is a app that shows me that i am now running at 1.6ghz or where I can see this?..on the max cpu it says 1.0ghz 1.385V. Thanks.
well...tegrak shows you that you what you are running. once you apply the tweak to level 0, make sure you apply it and let it watch the phone stability. once it is done, you can go back into tegrak and it should say it. make sure you are clicking on optimization to change your settings. also make sure your governor is on on demand and at least 200mhz if you are over 1.2 ghz
I just put the tegrak settings as dsexton had it as the following..i still see 1ghz even after changing the voltages and making it ondemand 200ghz..this is what i have..
level 0 1000 1385 1165
level 1 800 1075 1050
level 2 400 1000 1000
level 3 200 900 980
level 4 100 850 950...
just like dsexton has it in the kh1 thread..
you didnt change your frequency to 1600 in level 0. but remember. you shouldnt go straight to 1600. you have to gradually increase your OC. its like going from sitting down to a full sprint. you cant just sit for hours and then get up running. you have to warm up first and then hit your top speed. same concept. go to 1.1 to 1.2 until you get to 1.6.
ok i just changed it to 1100..so are u saying i should wait a day before i go to 1200 then another day 1300 and so on...how much far time apart till u think i should start increasing the voltage..
i would wait at least a couple of hours. a day should be sufficient, in my opinion, but i'm no expert.
I gave it a few hours before I went 1.6.
ok one other questions right now im on level 0 1100 1385 1165 on ICBBINKH1, can i use the same Core and Internal Voltages for frequency 1200 -1600? I dont want to have to reset all the values by default..I just used all the voltages that dsexton had on ICBBINKh1..I wasnt sure if he said to use 1385 and 1165 voltage ONLY on 1600 frequency??..
I would follow dsexton's, just to be safe. You can save your profiles also.
I dont see that on tegrak...how do you save your profiles?
Click on "Profile" right below "Load overclock module"
for some reason that is grayed out for me...
Are you using the free version?
i dont use profiles at all, but are you using the paid version? make sure your overclock module is loaded and it is set to apply on boot. you should be running 1.6 by this time tomorrow. dsexton lists all of the stable internal and core voltages in his thread
yeah its tegrak overclock ultimate 0.5.1.4...
I tried to search but was unsuccessful to find the information that I wanted.
Can someone tell me what are the recommended safe undervolt settings for the transformer?
I'm running prime 1.9 with clemsyn-blades 1.6a.
Thx
Sent from my Transformer TF101 using Tapatalk
steve.garon said:
I tried to search but was unsuccessful to find the information that I wanted.
Can someone tell me what are the recommended safe undervolt settings for the transformer?
I'm running prime 1.9 with clemsyn-blades 1.6a.
Thx
Sent from my Transformer TF101 using Tapatalk
Click to expand...
Click to collapse
I don't know what the stock settings are but I can tell you the process I followed when I OCed my tablet. Install the custom kernel and rom you want. Then install an app to modify frequency and voltages. I use setCPU but pimpmycpu works also.
1. Find the highest clock you can attain with the provided overvolt from the kernel. To do this just start at the highest frequency and see if the tablet reboots or locks during a stress test. Some people play games to stress. I use the built in stress tester in SetCPU. Make sure to apply the higher frequency for testing but not to apply settings on reboot or you could get stuck in a reboot loop (or so I am assuming the kernel might reset to 1 GHz when a hard lock occurs).
2. Once you have the maximum Frequency (for me it was 1.644 MHz) then start lowering the voltage for that frequency only until you loose stability. I can undervolt 1.644 by -75 mV. If I go upto -100 then I get random reboots. I go in -25 mV increments but you could narrow it down even more by going with -10 or even -5 intervals.
3. Take the offset you got (in my case -75 mV)on the highest frequency and apply it to every frequency above 1 GHz and see if this is stable. If not then slowely increase voltage until you gain stability again.
4. (Optional) Then start undervolting stock frequencies from 216 MHz to 1 GHz. Every tablet is different but (I have heard) this could cause sleep issues. I undervolted all frequencies from above 216 to 1000 GHz by -25 Mv without any issues. I may bring it down slowely by increments of-5 or -10 until I run into some issues.
5. (Optional) Undervolt 216 MHz as low as possible to save standby battery power. I undervolted my 216 MHz to 725 mV (even though SetCPu goes lower the kernel is locked at this). Which helps keep my battery levels up when the tablet screen is off and not in use.
Hints: To test that a voltage is okay at a certain frequency then make sure to set your max to the frequency level you want to test. If you set the max at 1544 and undervolt 1 GHz you will never know if it is okay because when you stress it it will blow right past 1 GHz upto 1544 and the voltage for that will take over.
If you have any questions please let me know.
Bjd223 said:
I don't know what the stock settings are but I can tell you the process I followed when I OCed my tablet. Install the custom kernel and rom you want. Then install an app to modify frequency and voltages. I use setCPU but pimpmycpu works also.
1. Find the highest clock you can attain with the provided overvolt from the kernel. To do this just start at the highest frequency and see if the tablet reboots or locks during a stress test. Some people play games to stress. I use the built in stress tester in SetCPU. Make sure to apply the higher frequency for testing but not to apply settings on reboot or you could get stuck in a reboot loop (or so I am assuming the kernel might reset to 1 GHz when a hard lock occurs).
2. Once you have the maximum Frequency (for me it was 1.644 MHz) then start lowering the voltage for that frequency only until you loose stability. I can undervolt 1.644 by -75 mV. If I go upto -100 then I get random reboots. I go in -25 mV increments but you could narrow it down even more by going with -10 or even -5 intervals.
3. Take the offset you got (in my case -75 mV)on the highest frequency and apply it to every frequency above 1 GHz and see if this is stable. If not then slowely increase voltage until you gain stability again.
4. (Optional) Then start undervolting stock frequencies from 216 MHz to 1 GHz. Every tablet is different but (I have heard) this could cause sleep issues. I undervolted all frequencies from above 216 to 1000 GHz by -25 Mv without any issues. I may bring it down slowely by increments of-5 or -10 until I run into some issues.
5. (Optional) Undervolt 216 MHz as low as possible to save standby battery power. I undervolted my 216 MHz to 725 mV (even though SetCPu goes lower the kernel is locked at this). Which helps keep my battery levels up when the tablet screen is off and not in use.
Hints: To test that a voltage is okay at a certain frequency then make sure to set your max to the frequency level you want to test. If you set the max at 1544 and undervolt 1 GHz you will never know if it is okay because when you stress it it will blow right past 1 GHz upto 1544 and the voltage for that will take over.
If you have any questions please let me know.
Click to expand...
Click to collapse
Cool. I'll give this a try.
Sent from my Nexus S using Tapatalk
I get a stable undervolt at -50 on all cpu steps which is pretty good. This should save loads of battery.
Sent from my Nexus S using Tapatalk
steve.garon said:
I get a stable undervolt at -50 on all cpu steps which is pretty good. This should save loads of battery.
Sent from my Nexus S using Tapatalk
Click to expand...
Click to collapse
I started at the top and went down every stepping from 1624 to 1000 and found out the lowest stable frequency and then added 10 to be safe to each one. I am currently at
1624 (-70)
1592 (-80)
1544 (-180)
1472 (-80)
1424 (-160)
1336 (-185)
1232 (-185)
1000 (- 110) which is 990 mV
I then set every stepping under 1 GHz frequency that was above 990 mV to 990 mV as if it can run at 1 GHz at that voltage then any speed under that will run fine at that voltage also. I have some more stability testing to do but I think I got it pretty much nailed down for my device. I may go through all the sub 1 GHz frequencies but it does take some time to run a stress test under each stepping.
Also I have never had any sleep issues but that is something to look out for. I also wonder how temperature affects stability as I have never gotten it above 40c. The pad might benefit from a 1 or 2mm thermal pad squeezed between the CPU and the back bezel (if it will fit).
Does anyone know that tjunction max for a Tegra2? I have a profile set up in SetCPU that sets the CPU frequency at 1 GHz if the CPU gets above 42 because I saw something similar in the Clemsyn rom but don't really know when the CPU will start to throttle itself at or shut off.
I am trying to find stock voltages for different devices because it seems like some mfgs are undervolting to save battery on some tablets.
Bjd223 said:
I started at the top and went down every stepping from 1624 to 1000 and found out the lowest stable frequency and then added 10 to be safe to each one. I am currently at
1624 (-70)
1592 (-80)
1544 (-180)
1472 (-80)
1424 (-160)
1336 (-185)
1232 (-185)
1000 (- 110) which is 990 mV
I then set every stepping under 1 GHz frequency that was above 990 mV to 990 mV as if it can run at 1 GHz at that voltage then any speed under that will run fine at that voltage also. I have some more stability testing to do but I think I got it pretty much nailed down for my device. I may go through all the sub 1 GHz frequencies but it does take some time to run a stress test under each stepping.
Also I have never had any sleep issues but that is something to look out for. I also wonder how temperature affects stability as I have never gotten it above 40c. The pad might benefit from a 1 or 2mm thermal pad squeezed between the CPU and the back bezel (if it will fit).
Does anyone know that tjunction max for a Tegra2? I have a profile set up in SetCPU that sets the CPU frequency at 1 GHz if the CPU gets above 42 because I saw something similar in the Clemsyn rom but don't really know when the CPU will start to throttle itself at or shut off.
I am trying to find stock voltages for different devices because it seems like some mfgs are undervolting to save battery on some tablets.
Click to expand...
Click to collapse
-180 in some frequencies!! Thats just insane. I've got to try this.
FYI, you don't have to lower voltage for all upper 1ghz frequencies. If your running at 1544 for exemple. The cpu will never touch the frequencies between 1000 and 1544. After the 1000 its a direct step to whatever frequency your overclocking too. You can monitor this in setcpu.
I cannot undervolt as precise as you can. For some reason setcpu only let me do 25mv increment...
Sent from my Nexus S using Tapatalk
I have undervolted by -175 on all frequencies, obviously 216Mhz is locked but all seems pretty stable after some testing. No sleep death either so I'm going to carry on testing.
steve.garon said:
-180 in some frequencies!! Thats just insane. I've got to try this.
FYI, you don't have to lower voltage for all upper 1ghz frequencies. If your running at 1544 for exemple. The cpu will never touch the frequencies between 1000 and 1544. After the 1000 its a direct step to whatever frequency your overclocking too. You can monitor this in setcpu.
I cannot undervolt as precise as you can. For some reason setcpu only let me do 25mv increment...
Sent from my Nexus S using Tapatalk
Click to expand...
Click to collapse
In SetCPU do not use the slider use the keyboard and type in the exact number you want.
I wanted to figure out every stepping in case I wanted to switch to a lower frequency but yeah most poeple don't have to do this.
The lowest stable I have gotten is -190 but feel like adding 10 padding will ensure stability.
I will probably do the sub 1 GHz frequencies today or tomorrow.
Bjd223 said:
In SetCPU do not use the slider use the keyboard and type in the exact number you want.
I wanted to figure out every stepping in case I wanted to switch to a lower frequency but yeah most poeple don't have to do this.
The lowest stable I have gotten is -190 but feel like adding 10 padding will ensure stability.
I will probably do the sub 1 GHz frequencies today or tomorrow.
Click to expand...
Click to collapse
I didnt even noticed I could use the keyboard...
I finally settled to -25 @216, -50 under 612 and -100 over 612. And everything is stable
Sent from my Nexus S using Tapatalk
I have tested each voltage. I am under the impression that 725 mV is the kernel minimum in the Clemsyn kernel so once I hit that I just set every frequency under that too 725. I will eventually go through and stress test every frequency @ 725 to make sure everything is a-okay but I am sure it is.
Here is my list incase anyone wants a place to start.
1680 MHz (-000) I can not overclock to this freuqency.
1624 MHz (-070) 1380 mV
1592 MHz (-080) 1345 mV
1544 MHz (-180) 1220 mV
1472 MHz (-080) 1220 mV
1424 MHz (-160) 1115 mV
1336 MHz (-185) 1065 mV
1232 MHz (-185) 990 mV
1000 MHz (-215) 885 mV
0912 MHz (-215) 835 mV
0816 MHz (-235) 790 mV
0760 MHz (-215) 760 mV
0608 MHz (-225) 725 mV
0456 MHz (-100) 725 mV
0312 MHz (-075) 725 mV
0216 MHz (-025) 725 mV
Clemsyn said the minimum mV in his kernel but I can't seem to find the thread, but I think it was 725. If I find out it is something lower I will go through the lower ones until I hit the minimum.
Also please note that everything above 1 GHz has +10 mV padding added to it above the lowest stable I could find. Everything below 1 GHz only has a +5 mV padding on it. So for example I actually hit a -240 w/o any issues @ 816 MHz.
I tested in +/-5 mV increments but if you wanted you could narrow it down even further.
EDIT: Also after some testing it looks like it does use frequencies between 1 GHz and your max. I have it set to 1644 and it does hit 1232 MHz occasionally.
Bjd223 said:
I don't know what the stock settings are but I can tell you the process I followed when I OCed my tablet. Install the custom kernel and rom you want. Then install an app to modify frequency and voltages. I use setCPU but pimpmycpu works also.
1. Find the highest clock you can attain with the provided overvolt from the kernel. To do this just start at the highest frequency and see if the tablet reboots or locks during a stress test. Some people play games to stress. I use the built in stress tester in SetCPU. Make sure to apply the higher frequency for testing but not to apply settings on reboot or you could get stuck in a reboot loop (or so I am assuming the kernel might reset to 1 GHz when a hard lock occurs).
2. Once you have the maximum Frequency (for me it was 1.644 MHz) then start lowering the voltage for that frequency only until you loose stability. I can undervolt 1.644 by -75 mV. If I go upto -100 then I get random reboots. I go in -25 mV increments but you could narrow it down even more by going with -10 or even -5 intervals.
3. Take the offset you got (in my case -75 mV)on the highest frequency and apply it to every frequency above 1 GHz and see if this is stable. If not then slowely increase voltage until you gain stability again.
4. (Optional) Then start undervolting stock frequencies from 216 MHz to 1 GHz. Every tablet is different but (I have heard) this could cause sleep issues. I undervolted all frequencies from above 216 to 1000 GHz by -25 Mv without any issues. I may bring it down slowely by increments of-5 or -10 until I run into some issues.
5. (Optional) Undervolt 216 MHz as low as possible to save standby battery power. I undervolted my 216 MHz to 725 mV (even though SetCPu goes lower the kernel is locked at this). Which helps keep my battery levels up when the tablet screen is off and not in use.
Hints: To test that a voltage is okay at a certain frequency then make sure to set your max to the frequency level you want to test. If you set the max at 1544 and undervolt 1 GHz you will never know if it is okay because when you stress it it will blow right past 1 GHz upto 1544 and the voltage for that will take over.
If you have any questions please let me know.
Click to expand...
Click to collapse
Thanks for this mate. I followed your guide exactly and I'm using clems 16? Kernel completely stable at all frequencies including the undervolting!
Based on my testing you need ~ a +15 to +25 mV over stable CPU voltage to get stable 3D GPU.
I found that I could run hours of "Stress CPU" without any issues at a voltage but during stressful 3D games that are using CPU + GPU cores, at that same frequency, the machine would FC the app, reboot or lock. I have also noticed that the closer you are to the stable voltage different things will happen.
Far off - machine will usually reboot
Closer - machine will usually hard lock
Even closer - Apps will FC, widgets will act strange (like invert colors, black blocks for backgrounds, etc.)
So what I do now is I test with Dungeon Defenders at the main menu. Its seems that if you can last 1 hr at the Dungeon Defenders menu you are GTG. If you actually play the game then 1 stage is what I use to test.
Bjd223 said:
I don't know what the stock settings are but I can tell you the process I followed when I OCed my tablet. Install the custom kernel and rom you want. Then install an app to modify frequency and voltages. I use setCPU but pimpmycpu works also.
1. Find the highest clock you can attain with the provided overvolt from the kernel. To do this just start at the highest frequency and see if the tablet reboots or locks during a stress test. Some people play games to stress. I use the built in stress tester in SetCPU. Make sure to apply the higher frequency for testing but not to apply settings on reboot or you could get stuck in a reboot loop (or so I am assuming the kernel might reset to 1 GHz when a hard lock occurs).
2. Once you have the maximum Frequency (for me it was 1.644 MHz) then start lowering the voltage for that frequency only until you loose stability. I can undervolt 1.644 by -75 mV. If I go upto -100 then I get random reboots. I go in -25 mV increments but you could narrow it down even more by going with -10 or even -5 intervals.
3. Take the offset you got (in my case -75 mV)on the highest frequency and apply it to every frequency above 1 GHz and see if this is stable. If not then slowely increase voltage until you gain stability again.
4. (Optional) Then start undervolting stock frequencies from 216 MHz to 1 GHz. Every tablet is different but (I have heard) this could cause sleep issues. I undervolted all frequencies from above 216 to 1000 GHz by -25 Mv without any issues. I may bring it down slowely by increments of-5 or -10 until I run into some issues.
5. (Optional) Undervolt 216 MHz as low as possible to save standby battery power. I undervolted my 216 MHz to 725 mV (even though SetCPu goes lower the kernel is locked at this). Which helps keep my battery levels up when the tablet screen is off and not in use.
Hints: To test that a voltage is okay at a certain frequency then make sure to set your max to the frequency level you want to test. If you set the max at 1544 and undervolt 1 GHz you will never know if it is okay because when you stress it it will blow right past 1 GHz upto 1544 and the voltage for that will take over.
If you have any questions please let me know.
Click to expand...
Click to collapse
I always wanted to learn more about the mV and CPU speed stuff. I always install rom, install kernel of the one I heard the better is and that's it. Never had touched the voltage measure in any of my android device. Yeah i know, so noob.
Thanks for this how to info, I think I will play around a bit later. Right now I'm struggling with my self on wish of the 3 roms available install and stay.
Had to remove undervolt this weekend since my camera wouldnt start anymore. I'll have to redo all the tests I was doing but test for camera too. The tablet would just freeze as soon as I opened the camera app
Sent from my Nexus S using Tapatalk
steve.garon said:
Had to remove undervolt this weekend since my camera wouldnt start anymore. I'll have to redo all the tests I was doing but test for camera too. The tablet would just freeze as soon as I opened the camera app
Sent from my Nexus S using Tapatalk
Click to expand...
Click to collapse
My camera does not work either. I just figured it was Clemsyns kernel not the OC. I don't know anything about cameras but maybe they use a lot of voltage so the voltage to the CPU dips.
I never used the camera personally, but I will test it some and see what additional mV you need over stable to get the camera working.
Also I noticed the more you undervolt (it seems to me) the harder it is to undock with an app open. usually instead of reloading they FC or lock the device so i just make sure to hit the home key before I undock then alt tab right back into the app.
Bjd223 said:
My camera does not work either. I just figured it was Clemsyns kernel not the OC. I don't know anything about cameras but maybe they use a lot of voltage so the voltage to the CPU dips.
I never used the camera personally, but I will test it some and see what additional mV you need over stable to get the camera working.
Also I noticed the more you undervolt (it seems to me) the harder it is to undock with an app open. usually instead of reloading they FC or lock the device so i just make sure to hit the home key before I undock then alt tab right back into the app.
Click to expand...
Click to collapse
My camera did not work at 912 MHz at stock voltage on 17b but now on 18 I can do my normal undervolt settings and the camera works fine.
Hi,
1) I have installed Kyorarom 0.5.2 OC kernel and here are my SetCPU profiles.
Main - Min: 300 Mhz, Max: 800Mhz
On Call - Min: 83, Max: 400, Priority: 100
Time - 11 PM to 6 AM - Min: 83, Max: 200, Priority: 99
Screen Off: Min: 83, Max: 400, Priority: 98.
My problem is, if I use my phone after 11PM, the time profile gets activated.
But when screen is on, I want to use the main profile. How can I do that?
2) Which governor has less stress on CPU? Conservative or Lagfree?
3) When in the main profile, my phone constantly runs at my max setting, (ie) 800 Mhz. It never runs lower than that. Why does it happen?
maverickgenius said:
Hi,
1) I have installed Kyorarom 0.5.2 OC kernel and here are my SetCPU profiles.
Main - Min: 300 Mhz, Max: 800Mhz
On Call - Min: 83, Max: 400, Priority: 100
Time - 11 PM to 6 AM - Min: 83, Max: 200, Priority: 99
Screen Off: Min: 83, Max: 400, Priority: 98.
My problem is, if I use my phone after 11PM, the time profile gets activated.
But when screen is on, I want to use the main profile. How can I do that?
2) Which governor has less stress on CPU? Conservative or Lagfree?
3) When in the main profile, my phone constantly runs at my max setting, (ie) 800 Mhz. It never runs lower than that. Why does it happen?
Click to expand...
Click to collapse
HI,
1) I dont think that's even possible man... would be nice though
2) conservative
3) how do you know that its for constant? and that's normal if you've chosen 'performance' gov'ner.
PersianSphinx said:
HI,
1) I dont think that's even possible man... would be nice though
2) conservative
3) how do you know that its for constant? and that's normal if you've chosen 'performance' gov'ner.
Click to expand...
Click to collapse
1) Okay. I thought that the main profile is something like a "screen on" profile, which would override all others.
3) I checked using CPU Spy. My phone is always at the highest frequency. I am using conservative.
try a different governor / kernel
maverickgenius said:
1) Okay. I thought that the main profile is something like a "screen on" profile, which would override all others.
3) I checked using CPU Spy. My phone is always at the highest frequency. I am using conservative.
Click to expand...
Click to collapse
I'm not sure about the constant 800. even if it is, as long as battery works well, everything is OK
PersianSphinx said:
I'm not sure about the constant 800. even if it is, as long as battery works well, everything is OK
Click to expand...
Click to collapse
Well, even if the battery works fine, running the processor constantly at 800 MHz will decrease its life.
Does your phone too behave the same way as mine?
maverickgenius said:
Well, even if the battery works fine, running the processor constantly at 800 MHz will decrease its life.
Does your phone too behave the same way as mine?
Click to expand...
Click to collapse
lol, how long are you planning to keep this phone? decreasing the life from 10 years to 8 wont bother me at all (I dont actually know the life)
PersianSphinx said:
lol, how long are you planning to keep this phone? decreasing the life from 10 years to 8 wont bother me at all (I dont actually know the life)
Click to expand...
Click to collapse
Agree with you on that point. But you still didn't answer my question
1) Not possible.
2) Conservative.
3) Problem with conservative governor in Kyoyakernel maybe.
Advice : - Always use On Demand.
Find Kryllios ROM instructioin, he have sugeested good settings to get maximum battery life...........
Max 300 - MHz and Min 1200 Mhz...what is this!
Hi, I have a Samsung Galaxy S II I9100G and rooted it with Kernel superatoms v3.0 XXLA1 and installed SetCPU 2.3.0.2 in it.
Now, when I set the max and min slider to 1200 MHz (with Governer hotplug) and goes back to the home screen, after that, when I again open SetCPU, the max slider gets to 300 MHz and the min to 1200 MHz (with Governer powersave).
What is this, man!!! How can the processor run with maximum speed of 300 MHz and the minimum of 1200 MHz ....
Plzz...I need help
I'm using stock emui on android 4.4.2. I recently rooted my phone and noticed that the cpu frequencies are really weird. First of all all cpu over/underclocking apps showed max of 1.3 Ghz and min of 1.2 Ghz. Shouldn't max be 1.7 Ghz? Even more weird was i couldn't change the frequencies to anything else. I wanted to reduce the heat that 1.2 Ghz min frequency causes and thats why I rooted in first place. I managed to get frequencies stay by using Trickster mod's freq lock. But I'm still wondering if its normal for my phone to get hot and can I set max freq to 7.8 Ghz for gaming? And no, the power saving thing aka phone manager doesn't change anything else but increase battery life when I disable it.
That's for the A7 cluster. A15 cluster goes up to 1,7 GHz.
Tup3x said:
That's for the A7 cluster. A15 cluster goes up to 1,7 GHz.
Click to expand...
Click to collapse
I just noticed in another cpu tweaking app that it showed only some of cores can go up to 1.7 Ghz and other only to 1.3 Ghz. This furthermore confirms it that only half of cores are cabable of 1.7 Ghz. http://www.devicespecifications.com/en/model-cpu/6dee2d53
Too bad this info isn't almost anywhere at all.