Overclocking and Custom Kernels

[evilhugbear]

Hey guys,

I'm thinking about trying out custom kernels in order to overclock. I just have a few questions, of course.

Which kernel is the best? I've heard good things about netarchy, and I think CFS seems better than BFS, IMO.
Version 1.3.9 of Netarchy's kernel works with Android 2.3.5, right? Have any of you used it with 2.3.5?

How safe is flashing custom kernels? Is it about as safe as flashing custom ROMs? If I have issues, I can always go to CWM and flash a backup ROM, right?

You can install them with ROM Manager, right? How would I go about doing that?

And finally, Is it really worth overclocking? I know with the Pre, stock 500MHz was terrible, but 1GHz was pretty amazing. Is there a noticeable difference between 1GHz stock vs 1.3 or 1.4GHz?

Thanks!

 

[decalex]

Hey guys,

I'm thinking about trying out custom kernels in order to overclock. I just have a few questions
Which kernel is the best? I've heard good things about netarchy, and I think CFS is better than BFS, IMO.
Version 1.3.9 of Netarchy's kernel works with Android 2.3.5, right? Have any of you used it with 2.3.5?
How safe is flashing custom kernels? Is it about as safe as flashing custom ROMs? If I have issues, I can always go to CWM and flash a backup ROM, right?
You can install them with ROM Manager, right? How would I go about doing that?
And finally, Is it really worth overclocking? I know with the Pre, stock 500MHz was terrible, but 1GHz was pretty amazing. Is there a noticeable difference between 1GHz stock vs 1.3 or 1.4GHz?

Thanks!

Gonna try to answer in order here

Best kernel..as you'll probably hear, is relative. IMO, Matrix Kernel has been the most stable for me-- given I'm running CyanogenMod7 (nightlies.. i.e. not the "stable" versions). I've been using Matr1x 5.5 CFS, which by default, overclocks to 1.2GHz. I think you can push it up to 1.4. For my phone and this kernel, 1.2 seems to be the magic speed. 1.3 and 1.4 gave me some reboot issues.

Until a few weeks ago, I had been using Netarchy (while on 2.3.4)-- and was mostly unstable for me, given my setup.
Netarchy's kernel version 1.3.8 and higher work on 2.3.4 and 2.3.5, although I haven't used it on 2.3.5 yet.

As far as "how safe" it is to flash kernels-- I think the best indicator is the general feeling in the thread where they're posted. Although people are running different setups, taking an average of their experiences, I think, is telling of what yours might be.

If I flash a kernel, and my phone starts bootlooping, I plug in my usb, adb reboot recovery (brings you into clockwork), I go to advanced, Fix Permissions, and reboot. If no usb, I just pull the battery, hold power and vol up, and do the same. If that's not successful, I have a backup of whatever previous kernel I was using on my sdcard, and I flash that one (after clearing Cache, and Advanced > Dalvik cache). You could also restore a nandroid backup in clockwork, but I'm blanking right now if that restores your kernel, but I think it does.

You can flash a kernel through ROM Manager (although I usually don't) by dropping the new kernel on your sdcard, then Flash ROM from sdcard. Check the clear Dalvik and backup if you want.

I definitely notice a difference between my stock CM7 kernel: 1GHz and Matr1x at 1.2. There's usually some battery life tradeoff, but it's worth it for me.

Last note, if you're flashing a ROM and a kernel, usually, you would do your CW wipe, if necessary, then flash the ROM, then flash the Kernel BEFORE rebooting.
Every time I flash a new CM7 nightly, I reflash the Matrix kernel this way-- as the new nightly rom restores the original kernel.

Matrix kernel 5.5: [KERNEL][ACS]*Matr1x* with BLN and voodoo v5.5 - xda-developers

Hope that helps

 

[evilhugbear]

Is there any reason you don't flash from ROM Manager? Also, is it safe for it to boot at 1.2GHz?

I already have CM7 on my phone, so I just go to ROM Manager and flash the kernel just like a ROM? I won't lose anything except cache, right?

And are you using the newest version, 5.5?

Thanks

 

[evilhugbear]

Is there still a slim chance of bricking? Is it about as dangerous as ROMs?

 

[digitalslacker]

+1 for Matr1x. I run 1.0 and it's still faster than CM7's 1.0 kernel.

.I like BFS kernels. Supposedly the difference is that BFS are snappier but take longer to boot? While CFS boot fast but don't feel as snappy. At least that's the non-technical answer I read once.

Flashing anything is dangerous if it goes wrong. Best bet is to make sure you have at least 40% battery and remember that even if you think the phone is bricked, most of the time it's fixable, just do some digging and you'll find a way to get it back up and running.

 

[evilhugbear]

+1 for Matr1x. I run 1.0 and it's still faster than CM7's 1.0 kernel.

.I like BFS kernels. Supposedly the difference is that BFS are snappier but take longer to boot? While CFS boot fast but don't feel as snappy. At least that's the non-technical answer I read once.

Flashing anything is dangerous if it goes wrong. Best bet is to make sure you have at least 40% battery and remember that even if you think the phone is bricked, most of the time it's fixable, just do some digging and you'll find a way to get it back up and running.

Whenever I flashed CM7 / backed up my ROMs, I always plugged into the wall just in case .

I'll try flashing Matr1x tomorrow, when I have more time to fix it if something goes wrong. I don't think it will, though xD.

Do you guys recommend SetCPU? Is it best to just leave it at 1.2, or should I try ondemand or screenstate or something? What is the minimum I should set the minimum speed to, if I do scaling?

Do I just drag the slider to adjust the speed?

Thanks again guys

 

[decalex]

If you're on CM7, don't use setcpu to overclock. Just use the CM Settings > Performance > CPU Settings that are built in. I'd let it run at the default 1.2GHz for a day... just to make sure it's stable.

Yes, ver 5.5 is what I've been using (cfs).

This is a really good, comprehensive kernel guide, btw:
theMikMik.com • View topic - [GUIDE] - Comprehensive User's Guide to Kernels

 

[evilhugbear]

If you're on CM7, don't use setcpu to overclock. Just use the CM Settings > Performance > CPU Settings that are built in. I'd let it run at the default 1.2GHz for a day... just to make sure it's stable.

Yes, ver 5.5 is what I've been using (cfs).

This is a really good, comprehensive kernel guide, btw:
theMikMik.com • View topic - [GUIDE] - Comprehensive User's Guide to Kernels

Okay, cool. I didn't know CM7 had that . If 1.2GHz is stable, what is the recommended min speed? Does CM7's CPU settings automatically change the voltage? What is the best governor?

Thanks for answering my huge amount of questions xD

 

[decalex]

mathkid has tweaked the voltages on matr1x-- I wouldn't mess with them at first. I think standard is 1200 overclock and 100 under. I use the ondemand governor-- which basically says 1200 OR 200 (in my case).
Smartass would scale in between. depends on your usage

 

[q711179]

Gonna try to answer in order here

Best kernel..as you'll probably hear, is relative. IMO, Matrix Kernel has been the most stable for me-- given I'm running CyanogenMod7 (nightlies.. i.e. not the "stable" versions). I've been using Matr1x 5.5 CFS, which by default, overclocks to 1.2GHz. I think you can push it up to 1.4. For my phone and this kernel, 1.2 seems to be the magic speed. 1.3 and 1.4 gave me some reboot issues.

Until a few weeks ago, I had been using Netarchy (while on 2.3.4)-- and was mostly unstable for me, given my setup.
Netarchy's kernel version 1.3.8 and higher work on 2.3.4 and 2.3.5, although I haven't used it on 2.3.5 yet.

As far as "how safe" it is to flash kernels-- I think the best indicator is the general feeling in the thread where they're posted. Although people are running different setups, taking an average of their experiences, I think, is telling of what yours might be.

If I flash a kernel, and my phone starts bootlooping, I plug in my usb, adb reboot recovery (brings you into clockwork), I go to advanced, Fix Permissions, and reboot. If no usb, I just pull the battery, hold power and vol up, and do the same. If that's not successful, I have a backup of whatever previous kernel I was using on my sdcard, and I flash that one (after clearing Cache, and Advanced > Dalvik cache). You could also restore a nandroid backup in clockwork, but I'm blanking right now if that restores your kernel, but I think it does.

You can flash a kernel through ROM Manager (although I usually don't) by dropping the new kernel on your sdcard, then Flash ROM from sdcard. Check the clear Dalvik and backup if you want.

I definitely notice a difference between my stock CM7 kernel: 1GHz and Matr1x at 1.2. There's usually some battery life tradeoff, but it's worth it for me.

Last note, if you're flashing a ROM and a kernel, usually, you would do your CW wipe, if necessary, then flash the ROM, then flash the Kernel BEFORE rebooting.
Every time I flash a new CM7 nightly, I reflash the Matrix kernel this way-- as the new nightly rom restores the original kernel.

Matrix kernel 5.5: [KERNEL][ACS]*Matr1x* with BLN and voodoo v5.5 - xda-developers

Hope that helps

Nice post. Contains lots of useful information and presented in a rare display of intelligence shown in many forums. I too am using Matrix kernel and have good success with it. Used it first time after the 2.3.5 update and Netarchy for some reason didn't allow for Wifi connect and haven't looked back since.

After installing new Kernel you can play with both overclocking and under-volting as well which may help improve battery life. You can use either SetCPU or Proton Voltage both can be obtained from the Market. The Proton app has suggestions for the undervolting settings but is worth experimenting if you like that sort of thing.

 

[evilhugbear]

Just flashed it with ROM Manager . So far so good!

Are there any apps that will allow me to see CPU Speed and temperature?

Thanks for all the help!

 

[digitalslacker]

Whenever I flashed CM7 / backed up my ROMs, I always plugged into the wall just in case .

I'll try flashing Matr1x tomorrow, when I have more time to fix it if something goes wrong. I don't think it will, though xD.

Do you guys recommend SetCPU? Is it best to just leave it at 1.2, or should I try ondemand or screenstate or something? What is the minimum I should set the minimum speed to, if I do scaling?

Do I just drag the slider to adjust the speed?

Thanks again guys

I like the SA gov but recently I have been having an issue with choppy audio (using spotify) when the screen shuts off. I had to switch over the OnDemand. Interactive has the same issues as the SA gov too but I understand they are similar.

I don't bother with SetCPU. The profiles are known to cause I believe battery life issues in CM7

 

[evilhugbear]

It ran fine throughout the night . I want to try going to 1.3GHz or 1.4GHz.

Do I just select the option and it automatically adjusts voltages? Or do I have to manually adjust the voltage ?

(I'm doing this in CM7's preferences, if that matters.)

 

[jholm7]

It ran fine throughout the night . I want to try going to 1.3GHz or 1.4GHz.

Do I just select the option and it automatically adjusts voltages? Or do I have to manually adjust the voltage ?

(I'm doing this in CM7's preferences, if that matters.)

Voltages are preset.

OC is fun for a minute but I've found that a nice under-clock is more advantageous. I run 90% of the time at 200-800MHz without any ill effects and a bit better battery life.

I use Oxygen, tried CM7, MIUI and Pete's but began and ended with Oxygen with netarchy bfs 1.3.9.

Sent from my Nexus S 4G using Tapatalk

 

[enik]

Just flashed it with ROM Manager . So far so good!

Are there any apps that will allow me to see CPU Speed and temperature?

Thanks for all the help!

I use cpu master free because set cpu is not worth the money

Sent from my A70S using Tapatalk