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[Q] Overclocking and voltage control

Can someone point me to where I can learn how to use set cpu and set voltage properly. Just installed superotimized kernel and wondering how to take full advantage of it

p4ranoid4ndroid said:
Can someone point me to where I can learn how to use set cpu and set voltage properly. Just installed superotimized kernel and wondering how to take full advantage of it
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overclocking is pre-enabled, under volting can be done through an app the link is in the thread. there are 2 settings. try about -50v each if that works fine bump one down to -75mv at a time. test the phone over a day or two and see how it runs, see if it has sleep death after a few periods of inactivity, especially extended periods, see if it has sleep death while charging, which seems to make a difference that will test the low setting.
see if the phone shuts down without freezing, and see if it shuts down without freezing while charging, the heat in the battery makes a big difference, play some 3d games. if you have freezing issues you can disable overclocking under different situation with set cpu or se t the volts to a more conservative setting.

Dani897 said:
overclocking is pre-enabled, under volting can be done through an app the link is in the thread. there are 2 settings. try about -50v each if that works fine bump one down to -75mv at a time. test the phone over a day or two and see how it runs, see if it has sleep death after a few periods of inactivity, especially extended periods, see if it has sleep death while charging, which seems to make a difference that will test the low setting.
see if the phone shuts down without freezing, and see if it shuts down without freezing while charging, the heat in the battery makes a big difference, play some 3d games. if you have freezing issues you can disable overclocking under different situation with set cpu or se t the volts to a more conservative setting.
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I've been told that undervolting can improve the battery time. Of course, lots of varying opinions of how good/bad it may be to overclock.
If I want to just undervolt, is that possible with SetCPU?

Dani897 said:
overclocking is pre-enabled, under volting can be done through an app the link is in the thread. there are 2 settings. try about -50v each if that works fine bump one down to -75mv at a time. test the phone over a day or two and see how it runs, see if it has sleep death after a few periods of inactivity, especially extended periods, see if it has sleep death while charging, which seems to make a difference that will test the low setting.
see if the phone shuts down without freezing, and see if it shuts down without freezing while charging, the heat in the battery makes a big difference, play some 3d games. if you have freezing issues you can disable overclocking under different situation with set cpu or se t the volts to a more conservative setting.
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ewingr said:
I've been told that undervolting can improve the battery time. Of course, lots of varying opinions of how good/bad it may be to overclock.
If I want to just undervolt, is that possible with SetCPU?
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Interesting stuff...
I too would like to know if it is possible to simply under-volt. Does anyone know the optimal settings for SetCpu with the Captivate...or does it vary depending on each users profile/ phones?

So Ive been playing around with various settings for set cpu and voltage control and all has been well so far. The only problem im having is voltage control seems broke. I try to open the all but it just black screens. I tried to clear the memory and unistall and reinstall and still have the same problem. Any ideas?

http://forum.xda-developers.com/attachment.php?attachmentid=432086&d=1288709102
^you can under volt setirons kernel and disable overclocking with this app.
i find my battery life to be less than stock with this kernel, i need to see if it is a common issue, maybe because it is not a captivate kernel. but in the past with unhelpfuls kernel for 2.1 battery life was awesome.

spartan062984 said:
Interesting stuff...
I too would like to know if it is possible to simply under-volt. Does anyone know the optimal settings for SetCpu with the Captivate...or does it vary depending on each users profile/ phones?
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It's going to depend on the individual CPU in your phone. Your best result is to start at a given clock speed and begin lowering voltage in the smallest step possible, test for stability, repeat until you begin to notice instability (or you just run out of voltage options). You can just undervolt without increasing clock speed any, or you can not undervolt yet raise clock speed, or you can overclock and undervolt, depending on how your particular chip reacts. Some might need additional voltage to stabilize the snapdragon at 1.2Ghz while others (mine for example) is stable Able @ -100mV and 1.2Ghz. Overclocking silicon is the ultimate in YMMV.
Another thing to bear in mind is that increasing clock speed necessarily increases power consumption. There is no way around this. So a chip at 1.2Ghz will use more juice than 1Ghz even with the same voltage. It's difficult to say at this point whether, say, the Snapdragon @ 1.2Ghz and -100mV uses more or less power than the same chip @1Ghz and stock voltage. It's absolutely possible that the former uses more power, which would explain why you see at least one claim here of battery life decreasing even when voltage settings are left untouched.

hawkeyefan said:
It's going to depend on the individual CPU in your phone. Your best result is to start at a given clock speed and begin lowering voltage in the smallest step possible, test for stability, repeat until you begin to notice instability (or you just run out of voltage options). You can just undervolt without increasing clock speed any, or you can not undervolt yet raise clock speed, or you can overclock and undervolt, depending on how your particular chip reacts. Some might need additional voltage to stabilize the snapdragon at 1.2Ghz while others (mine for example) is stable Able @ -100mV and 1.2Ghz. Overclocking silicon is the ultimate in YMMV.
Another thing to bear in mind is that increasing clock speed necessarily increases power consumption. There is no way around this. So a chip at 1.2Ghz will use more juice than 1Ghz even with the same voltage. It's difficult to say at this point whether, say, the Snapdragon @ 1.2Ghz and -100mV uses more or less power than the same chip @1Ghz and stock voltage. It's absolutely possible that the former uses more power, which would explain why you see at least one claim here of battery life decreasing even when voltage settings are left untouched.
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Thanks for clarifying Hawkeye! I will report back on in a few days once i have tested out a few profiles. In my opinion, I feel that it is best to leave Over-clocking at default and maximize battery utilization with setcpu. However, the thought of over-clocking the Dragon beast is VERY tempting. Who wouldn't? I will definitely check out the differences when playing games and such.

spartan062984 said:
Thanks for clarifying Hawkeye! I will report back on in a few days once i have tested out a few profiles. In my opinion, I feel that it is best to leave Over-clocking at default and maximize battery utilization with setcpu. However, the thought of over-clocking the Dragon beast is VERY tempting. Who wouldn't? I will definitely check out the differences when playing games and such.
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I have to tell you, I'm not personally very fond of SetCPU on this device, even though I paid for the app (ugh). With raspdeep's voltage control app and SetIron's OC/UV kernel, the CPU defaults to 1.2Ghz at stock voltage, which for a basic setup is fine. Voltage Control app is phenomenal for adjusting in increments of 25mv at a time...one setting is for high clocks (1Ghz - 1.2Ghz) and the other is for < 1Ghz. It's probably best actually to start with the lower clock setting in Voltage Control, as your phone will spend the lion's share of it's time at those clocks and so that is where you should see the most gain in battery life. My only gripe is that I can't get the boot settings to stick on the Captivate so I have to go in and adjust them each time I reboot the phone. no biggie there.
SetCPU, on the other hand, has caused me loads of problems in the past, including causing the phone not to wake up from sleep and just atrocious battery life, I assume from constantly polling the CPU clock to measure clock speed. I have not experienced any of that with Overclock Widget, but I also don't use any of the independent clockspeed controls in the app...basically it's just a widget to display clock speed the way I use it. Otherwise, Setiron's kernel gives the 200mhz overclock and I just let the Hummingbird deal with changing clocks on its own. Jmo, but it works for me with no resulting battery drain beyond the additional I expect as a result of the extra 200mhz.
edit: whoops, long day. hummingbird in my post from above, not snapdragon. I need a drinky poo.

hawkeyefan said:
I have to tell you, I'm not personally very fond of SetCPU on this device, even though I paid for the app (ugh). With raspdeep's voltage control app and SetIron's OC/UV kernel, the CPU defaults to 1.2Ghz at stock voltage, which for a basic setup is fine. Voltage Control app is phenomenal for adjusting in increments of 25mv at a time...one setting is for high clocks (1Ghz - 1.2Ghz) and the other is for < 1Ghz. It's probably best actually to start with the lower clock setting in Voltage Control, as your phone will spend the lion's share of it's time at those clocks and so that is where you should see the most gain in battery life. My only gripe is that I can't get the boot settings to stick on the Captivate so I have to go in and adjust them each time I reboot the phone. no biggie there.
SetCPU, on the other hand, has caused me loads of problems in the past, including causing the phone not to wake up from sleep and just atrocious battery life, I assume from constantly polling the CPU clock to measure clock speed. I have not experienced any of that with Overclock Widget, but I also don't use any of the independent clockspeed controls in the app...basically it's just a widget to display clock speed the way I use it. Otherwise, Setiron's kernel gives the 200mhz overclock and I just let the Hummingbird deal with changing clocks on its own. Jmo, but it works for me with no resulting battery drain beyond the additional I expect as a result of the extra 200mhz.
edit: whoops, long day. hummingbird in my post from above, not snapdragon. I need a drinky poo.
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LOL. No Worries. I myself made the same mistake. I thought something was odd with my post. SnapDragon...Hummingbird....Bulbasaur.....I knew what you meant. lol

Still not having any luck with the voltage control app. Ive tried flashing different roms to see if it would work. I undervolted it to 100/75 the first time i did it and now i cant change. Only a little worried

i guess there was an issue with the set on boot scripts not working. supposedly that is fixed, i dont know for sure though, i haven't updated.

From what I'm gathering, in order to undervolt, you must have a kernel to su pport that, for example Setirons.
I'm not necessarily interested in overclocking, as it performs well as is. Of course there are arguments that overclocking may ultimately harm the phone, and arguments that by the time that happens, you'd be ready for a new phone. In any event, if I start getting slower, I may interest in overclocking.
Does anyone know if dramatic improvement in battery performance with underclocking?

I've noticed quite a bit of a difference, just pretty difficult to tune it precisely. (Coming from a person who enjoys overclocking computers a little too much). I just wish there was an app that would test each frequency and then let you know which one failed (without having to manually set it).

[Q] Overclocking cm7 to 1600 Mhz

So overclocking cm7 to 1600 doesnt work and causes boot loops, i have been trying to get a kernel that would do it and i cant find one.
anyone know any kernels that work?

Only kernal for cm7 is the one that is with it no other kernals are compatible as for 1600 some phones run fine at 1600 others don't just depends on your CPU in your phone
Sent from my SGH-I997 using xda premium

^^^ what he said ^^^
my cappy was maginally stable @ 1300 within a very narrow voltage range. my infuse runs 100% @ 1664 with a ton of uv untill i turn on gps and everything starts to get warm. every cpu is different.
most infuses seem to be a higher test cpu than galaxy s phones though. you may be able to run at 1500 or better if you take a lot of time and figure out what the cpu likes and doesnt like. remember heat, uv and rapid voltage change can all cause instability so too much uv can cause problems as well as too little! to get maximum speed you may want keep the top few freq's at the same voltage (not the same uv but the same actual voltage) and have zero uv on the low freq's. it can be a pain to figure it all out but when you see the benchmarks you may think it was worth it.

ok well i kinda messed around with the overclocking built in and was messing with the type of governors and userspace seems to support over clocking on 1600.
really weird but my phone hasnt done the boot loop yet.
but thanks for your guy's help.

I set mine at 1600 last night via SetCPU. After 5 min it got hot and started boot looping. Its running good at 1200 now. I'm gonna bump it up little by little.
Good info, nice to know its "normal".

Honestly, the performance of CM7 outperforms all the other ROMS even running at 1.2GHz (IMO). I really don't see much of a performance increase by stepping up the clock speed, just a decrease in battery life, so it's not worth it to me.

ive talked to many people about this and most can only run at 1.4ghz even though 1.6ghz was stable in froyo. alot of people repeat "it depends on your specific chipset" but i dont buy that cop out. i think theres something wrong with the 1.6ghz setting in cm7.

[Q] With LiveOC I must change also the voltages?

Hi there!
I'm not allowed yet to post in the development section, so I decided to put my question here... Please don't shoot me
I have read many threads from the Development Section (when got the time), tested a few Roms and Kernels. All of the developers are doing a great job, every day (my donations are going to eugene373, mathkid95 & peter alfonso).
I had no idea how a Nexus S can "move" with a custom Rom or Kernel.
I'm kinda new in this "root affair" with my phone, and i found a superb combination between Bugless Beast Rom & Matr1x 15 Kernel. For that i have posted some screen shots.
In order to achieve those results, i used LiveOC to 105 but i didn't changed the voltages. Oh, and Lulzactive/Sio. When i put the phone to charge, i had a freeze, and a battery pull was needed.
So, can someone tell me if i need to change the voltages too for that combination to be stable? If so, which are the best voltages?
Thank all of you in advance!
P.S.: I use i9023 LCD. With eugene373's Speedy 7 & stock ICS i had no reboots or freezes, but the battery is not that great. Although, the phone is unbelievably fast.

They're decent results, the i9023's screen generally uses more power due to the backlight. Matr1x kernel is undervolted and some phones don't like it. For LiveOC i would DEFINITELY pump up the voltages (say +25mV across the board, except 100mhz and 200mhz as matr1x has them stock). Keep messing around with the voltages until you find the lowest voltage that is happily stable and not overheating.
Your phone may be fine, though. But as the frequency goes up AND matr1x is already undervolted, you'll probably be better off taking it up to 110% and finding somewhere stable there since i believe the minimum voltage change is 25mV.

Thank you very much for your answer.
I'll will try to do what you adviced me, but I'm a little bit afraid not to mess up things because I'm just a begginer, as I said...
Best of luck!

You'll be fine mate, just don't push it too hard until you know what your phone is capable of and make sure heat isn't a problem. Some chips just aren't as lenient as others, but yours seems to take undervolting fairly well which is a good sign.

Also, as you're bumping it up and testing, don't check set on boot. Unless you have a current working nandroid at least.
Sent from my Nexus S 4G using xda premium

Harbb said:
They're decent results, the i9023's screen generally uses more power due to the backlight. Matr1x kernel is undervolted and some phones don't like it. For LiveOC i would DEFINITELY pump up the voltages (say +25mV across the board, except 100mhz and 200mhz as matr1x has them stock). Keep messing around with the voltages until you find the lowest voltage that is happily stable and not overheating.
Your phone may be fine, though. But as the frequency goes up AND matr1x is already undervolted, you'll probably be better off taking it up to 110% and finding somewhere stable there since i believe the minimum voltage change is 25mV.
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i think your statment about screen is not completely right.
yes , based on SA screen functionality , it's saves more power then Super Clear LCD screen because SA lights its up by itself , but SC LCD screen needs additional light lay.
but that also depends on color , SA runs brilliant color costs same , or even more juices as SC LCD , but it do save power when shows dark color like black.
this is why android 2.3 status bar color has changed from grey to black , also default wallpaper for Nexus S is dark color.
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to OP , about voltages , you only have to change it when you OC and your phone become unstable , live OC usually are able up to 115% or 120% , if you don't OC over 1.0 G but use live OC up to 1.15 G or 1.2 G , you won't be needing change voltage.
but if you use both OC and liveOC , for example by Matr1x, CPU can set up to 1.46G and 115% of LiveOC , max to 1.67 G , in that case you may need change voltage...
yes... this is max i've done , i was afraid that i would get CPU fried...

I said generally for the amoleds, I'm very aware of how they work. Unless you're staring at an all white screen all day it is quite rare for it to use more power. This is why it is a great technology for mobile phones.
Anywho, it certainly needs additional voltage with liveoc. Please don't misinform others. At 110%, 1GHz becomes 1.1GHz which is plenty to cause instability on many cpus. This is especially true with matr1x and other undervolted kernels.

with all due respect , but i think little bite OC doesn't really need change voltage , because usually , generally , mostly , kernel default setting is enough...

When you live oc an undervolted kernel yes you do need to raise voltages
Regardless if you regular oc or not because if you live oc by 10% you are ocing by 10%. Its not complicated.
Harbb is right.
I know, I'm a tester for matr1x and in being a tester that means I have to test all aspects of it and put it under different strains, overclocking etc.
To the OP:
Live oc by 110% and if you have problems with reboots then raise voltages by 25mv as harbb said already.
And he also gave good advice regarding unchecking the set at boot option in nstools.
Disregard all other comments.

Thank you Harbb and Nodstuff!
Very good advices, I've followed them and seems to work ok so far. Seems like I didn't read that much as I thought, because I didn't know that the Matr1x kernel is undervolted. I have to read more infos from here, wish I'd had the time... I was just looking for a good combination between a Rom and a Kernel, because I had terrible battery life on stock ICS. Now I'm pretty happy with the combo mentioned above, thank you again for your help.
I wish you all the best and good luck!

[Q] Difference between under-clocking and under-volting

I'm using the Faux Kernel on my Skyrocket. I'm using Set CPU for speed control, under-clocking for more battery life.
I head the terms UC, OC, UV and OC. When I use Set CPU, I assume that when I set maximum CPU speeds, I'm under-clocking. But what is under-volting? Is that different? Is there an advantage to doing both?
Harry

There is an advantage to undervolting you need either fauxs app or systemmtuner to do so.
Undervolting is giving the cpu less power and asking it to do the same amount of work it was doing before
Sent from my GT-P7500 using xda premium

That sounds a bit more dangerous in terms of doing damage to the phone or having reboots etc. when you are giving the circuity less power than it was designed.
For those who chose to undervolt for power savings, it is usually done in conjunction with under-clocking, or is it a one or the other type thing?

Not really, under volting is not as dangerous as over volting (used to also achieve higher overclocks). Over volting can actually damage hardware if you provide too much juice.
Under volting just reduces the voltage, if its not enough the app freezes or worse the phone reboots. If that happens, bump it up one more step (+12500) and you should be fine. Find where you can go low but still be stable (for me it happens to be -87500) you will save more battery.
Dixit

all good correct info. I highly recommend fauxclock, its very user friendly. I have my phone undervolted -100mV and underclocked to 1.2 and I'm getting 13 hours heavy usage with around 5 hours on screen time, with NO juice defender. For this phone, that's pretty good

icenight89 said:
all good correct info. I highly recommend fauxclock, its very user friendly. I have my phone undervolted -100mV and underclocked to 1.2 and I'm getting 13 hours heavy usage with around 5 hours on screen time, with NO juice defender. For this phone, that's pretty good
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My exact setup. -100mV UV, and 1.188 gHz UC. Went from 100% to 0% in 1 day 7.5 hours with 3 hours of screen on time. No juice defender either. I think its pretty food. Using faux 009u, btw.
Sent from my SAMSUNG-SGH-I727 using XDA

Only issue I got with Fauxclock is that it saves the CPU clocks I set (say 1.298ghz max) but it doesnt actually save the voltage after a reboot. I look at the VDD table and its still stock.
So only way to get it to work is to manually edit the VDD table itself. Not sure if this is by default that fauxclock doesnt actually save the voltages after a reboot.
Dixit

Don't see fauxclock in the application store, sorry, Google Play Station.

Thats cause its not in the Google Play. Its a separate app at this location
http://rootzwiki.com/topic/4550-app09-beta-snapdragon-dual-core-oc-control/
Dixit

Got it, thanks. And the under-volting is so easy with Fauxclock, I've set it down 100.
So I've got SetCPU doing the CPU speed, and Faux for the voltage. Seems a bit redundant, since Faux also does CPU speeds, but SetCPU has some cool configuration settings where you can actually have multiple settings for CPU speed based on various conditions such as battery life remaining, processor temperature, time of day, phases of the moon . So I guess I have to keep them both. Hope they don't interfere with each other.

Fauxclock has very basic CPU clock settings, it was created just for that faux compatible kernels so the original developer didnt spend weeks on it. It was just a simple and fast and effective GUI to set min/max clocks and also voltages (global scale). You can however set one other clock which is the "screen off" clock, but thats about it.

harry_fine said:
Got it, thanks. And the under-volting is so easy with Fauxclock, I've set it down 100.
So I've got SetCPU doing the CPU speed, and Faux for the voltage. Seems a bit redundant, since Faux also does CPU speeds, but SetCPU has some cool configuration settings where you can actually have multiple settings for CPU speed based on various conditions such as battery life remaining, processor temperature, time of day, phases of the moon . So I guess I have to keep them both. Hope they don't interfere with each other.
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they will, use one or the other. U can manually change global vdd table and use setcpu, or forego advanced profiles in setcpu, but u can't/shouldn't use both

FauxClock force closes on launch for me..
EDIT: Getting a Faux kernal fixed that. Wow I feel dumb.

Shadeslayers said:
FauxClock force closes on launch for me..
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Are u using faux kernel?

Any tips or thread about how to manually change global vdd table so that I can use SetCPU for the profiles and adjust voltage manually?
Is there a risk to that? If I set it and the phone won't boot, it sticks!

use Gideon UV/OC script and change vdd as u see fit. If it doesn't work u can always flash Gideon stock back

icenight89 said:
use Gideon UV/OC script and change bed as u see fit. If it doesn't work u can always flash Gideon stock back
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What exactly is the difference between flashing Gideon's script or just using FauxClock? Thanks!

fauxclock gives u dynamic min/Max and voltage control as per user settings. Gideon is pre-set and makes use of init.d script. u can change it, but every change requires a reboot

pros and cons OC/UV

about time for me to change roms again. i know there are many with this option, but have never chose to pursue that option due to lack of understanding benefits. always seemed to get satisfactory battery life out of phone, but could it be better? i have noticed different speeds on my phone with different roms but is this something that can speed up and keep the smooooth in my phone?
just thought i would get some feedback of the advantages and disadvantages of overclocking and undervolting.
will it harm my infuse?
what are good settings?
what exactly would the OC or UV each do?
if i run a search on this, i know i am going to get the phone book and just figured i would get a more specific answer directly as opposed to piecing little bits together and still not being confident in what my interpretation would be.
everyone in the infuse community always seems to have the answers and dont steer the dullards such as myself in the wrong direction.
you guys are the MAN, and well, you women.....your the woman i reckon

captemo said:
will it harm my infuse?
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No, so significant damage can be done with overclocking. Alhought if you set your ghz too high your phone might become unresponsive, overheat and/or auto reboot your device. This is normal if your on GB and some ICS roms. Don't see it much on JB becuase the some kernels dont support it. Just be sure to play with your settings and MAKE SURE SET ON BOOT IS DISABLED or else your phone will be stuck in a bootloop when overclocked beyond stable settings.
captemo said:
what are good settings?
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I usually stick with 1400 ghz because 1600 ghz[max] drains battery too quickly for not much of performance boost and 1600 is considered unstable on most GB and ICS roms. As for CPU governor Id stick with ONDEMAND.
captemo said:
what exactly would the OC or UV each do?
Click to expand...
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OC is over clocking your processor to a higher ghz for better perofmance and under volting is drawing less energy

Is there like a guide saying what each CPU governor does? Because some of them are pretty confusing with their terminology, like smartassv2

Garen21 said:
Is there like a guide saying what each CPU governor does? Because some of them are pretty confusing with their terminology, like smartassv2
Click to expand...
Click to collapse
http://forum.xda-developers.com/showthread.php?t=1420742

I used to under volt a lot to get better battery life. But it seemed to make a couple apps hang now and then.
I am now on Scotts PA JellyBean ROM. Battery life is very good for me stock with this. So I have left under volt to stock settings.
Normally I'll run on smartassV2 governer. With NOOP i/o. And 100mhz - 1400mhz.. just for a little extra boost.
When I know I'll be playing a game or multitasking, I'll boost it to 1600mhz.
Overall stock settings run amazing, both battery life and performance, on Scott's PA JB and CM10.
After doing some reading, I believe I can get better results from using the above settings. It all depends on what your personal goal is.
The biggest concern you should have when overclocking is mentioned above. Boot loop, just make sure you test it for a while with set on boot un checked.
Undervolting you can go to low and also boot loop, so same applies here... leave set on boot un checked. All phones are different on what settings they run best at. Just gotta play around and see what works for you.
A good rule of thumb for under voting... go down 25mv at a time and test it out... keep going down 25mv until you get a problem or boot loop and then go back.. then you'll know your max.
You can safely under volt more on the lower frequencies than you can the higher ones. Personally I never undervolted more than 100mv across the board. And when I did, I usually kept it around -50mv.
Sent from my SGH-I997 using xda app-developers app

not for infuse but a good reference for ocuv. explains what they do
http://forum.xda-developers.com/showthread.php?t=1827635
Sent from my GT-I9300 using xda premium

This is the best guide I've found covering kernel and system tuning - CPU parameters, governors, schedulers, init.d, loadable modules, etc. It's for the SGS2 (i9000) and some of the governors/schedulers are not available on the Infuse, but much of this is applicable to our phone:
http://forum.xda-developers.com/showthread.php?t=1369817
As for OC/UV, as long as you stay away from the "Performance" governor (this runs the phone at max freq all the time), and undervolting below -75 to -100 you generally will be safe. As phones are different, it is important to test in gradual steps to ensure your phone will be reliable. Use a good CPU manager, like SetCPU, Antutu, or Voltage Control. Make sure you enable the "revert to stock" feature so that you can boot recovery and turn off any bad OC/UV. As noted above, do not check the enable on boot setting until you are certain you have a good config.
The decision to OC should take into account how you use the phone. If your phone is asleep more than 80% of the time on average, you can probably run an OC config and still have overall good battery life (i.e. lasting an entire day with nightly recharges). If you use your phone for music playback or something else that prevents it from sleeping, OC may not be for you. If you run CPU intensive games, it is better to disable UV settings while OCed.
Use CPU Spy to keep an eye on your time at each freq state (and sleep). Use the default battery stats and graph to monitor which apps are consuming the most battery. Use apps like Better Battery Stats, Android Assistant and Watchdog for more detailed monitoring of what is keeping the phone awake and which apps/processes are top cpu resource consumers. With this information you can identify problem apps and decide whether you should remove them from your phone.
From the "unintended functionality" side of the house, there are certain tweaks that will cause your phone to run at max freq ... mucking around with phone properties in build.prop can lead to runaway rild process problems (usually shows up as unusually high "Dialer" in the standard battery stats list and a phone that is warm or hot to the touch). Some of the tweak scripts in adrenaline and tbolt can cause similar problems. There is a known bug in the infuse network drivers that shows up as much higher than normal Android OS battery usage. This can usually be corrected (short term fix) by toggling Flight/Airplane mode off/on. Running the stock UCLB3 GB kernel also seems to minimize this issue (assuming you are running a GB ROM), but flash with caution as you will need to disable voodoo lagfix first. (You will also lose CWM recovery, OC/UV capability, and be on the slower stock file system setup).

I have done a fair amount of experimenting including lots of time on conservative governor with Fmax=1600 and never had any problem that I attributed to OC'ing.
In contrast I did find a limit on UVing. I just updated my thread with my experience on uv here:
http://forum.xda-developers.com/showthread.php?p=32552571#post32552571
The bottom line is that for MY phone, the following works fine:
100 Mhz: 950mv max – 50mv = 900 millivolts
200 Mhz: 950mv max – 25= 925 millivolts
400 Mhz: 1050mv max – 50mv = 1000 millivolts
800 Mhz: 1200mv max – 75 mv = 1125 millivolts
1200 Mhz: 1275mv max – 50mv = 1225 millivolts
1600 Mhz: 1400mv max – 75mv = 1325 millivolts
Some other links with others' experience suggestions about UV'ing for Infuse:
Hozw low is your undervolt?
http://forum.xda-developers.com/showthread.php?t=1693689&highlight=kernel
[Q] Recommended SetCPU settings?
http://forum.xda-developers.com/showthread.php?t=1292836&highlight=setcpu
You’ll note the last thread has comments from Entropy’s settings.
Also Zen and qkster gave advice in the first thread (my thread).
All three guys very well respected and worth listening to.
Entropy mentioned you can uv the higher frequencies more than the lower (different than what was posted earlier in this thread). I don’t know for sure but I’d lean toward Entropy’s advice on that matter.
I think all in all somewhere between 50 and 100 is the max you can expect to undervolt.
What can be achieved varies with phone as stated by many.
You are welcome to experiment with slowly decreasing. That's what I did.
But in the benefit of hindsight, the process of slowly decreasing is tedious. And going beyond the limit was a little scarey for me. Could've been worse if the phone crapped out at a critical time during "experimenting". Like almost everything related to battery life, the results (how much benefit) seem y subjective (difficult to measure quantitatively). Most people say they don’t notice a dramatic difference with UV. If you want to get the low hanging fruit without a lot effort, you might just try 50 down. That's what I'd do if I had to do it all over again.
By the way, setcpu can be set up to provide a failsafe escape route even if you go overboard. There is a zip file that will toggle the setcpu settings off when launched from CWM. You just have to put the zip file on your sd card before you start tweaking. See "safe mode" in the setcpu documentation.

started to wonder at first whether i would get any responses after 218 views and nothing, but i knew the community would come through as they always do. all the regulars as usual regulars ( Zen, Quickster and others) are always eager to help. i think you have all provided me with the valuable info i requested.
thank you much party people