[KERNEL] SpeedMod Captivate [K13E HPCall VoodooSnd7 SharpnessFix STABLE]


Senior Member
Sep 12, 2006
The original SpeedMod kernel, now available for AT&T Captivate users! This kernel aims to be fast, compatible, stable, and have good battery life. It makes our Galaxy S run the way it should.

This kernel is for the AT&T Captivate (SGH-i897)

The forum thread for the GT-I9000 version is here: http://forum.xda-developers.com/showthread.php?t=822756

WARNING: Before you try any lagfix, make sure that you have enough free space on your Internal SD. You should have at least more free space than data+dbdata+cache combined.

Latest K13E (12-Apr) - Voodoo Sound v7. Lowmemorykiller fixes. Improved display sharpness using AMOLED processing mode in MDNIE. Support for voice calls through headphones. Check here for more info and downloads.

Thanks to sasovics and rpicaso for the I897 boot logo!

>>> Click here for the installation procedure using Odin.

>>> If you have questions, please read the FAQ: Frequently Asked Questions first!

>>> What is the SpeedMod kernel?

Latest features:

- Compiled using codesourcery 2010.09: Faster and more battery efficient
- The only properly working Tiny RCU implementation, thanks to Paul McKenney
- More efficient: Removed debug logging from kernel and Android
- Most updated version of my Enhanced Universal Lagfix fork with improved stability
- Full Android 2.2.1 ROM compatibility

This kernel has:

- Based on JPX Android 2.2.1 kernel source
- Works on all stock Froyo 2.2 and 2.2.1 ROMs and popular custom ROMs
- 340MB RAM and all features should work
- Enhanced version of sztupy's Universal Lagfix
- Includes neldar's BackLightNotification 2.3 from https://github.com/project-voodoo/backlightnotification/tree/master/kernel_patches/
- Sharpness (AMOLED mode) & color fixes for the screen
- SpeedMod: Replaced kernel jhash2 with jhash3
- Includes my Startup Tweaks from http://forum.xda-developers.com/showthread.php?t=813309
- Adjusted kernel HZ value to improve smoothness
- Uses BFQ IO scheduler by default, from http://algo.ing.unimo.it/people/paolo/disk_sched/sources.php
- Updated ext4 code in kernel from http://www2.kernel.org/pub/linux/kernel/people/tytso/ext4-patches/
- Properly working Tiny RCU patch for better speed and efficiency from http://android.git.kernel.org/?p=ke...it;h=9b1d82fa1611706fa7ee1505f290160a18caf95d
- Patched lowmemorykiller for compatibility with Tiny RCU from http://android.git.kernel.org/?p=ke...ff;h=5545554aac04918ece318270d63cbfcb015577a9
- Optimized compiler flags: -O2 -mcpu=cortex-a8 -mfpu=neon -mfloat-abi=softfp



This kernel is based on sztupy's Universal Lagfix: Lagfix and root options are accessible by booting into the Recovery Menu.

To get the best speed, it is recommended that you enable all Tweaks from the Recovery Menu. Tweaks are under SpeedMod features. Info on Tweaks: http://forum.xda-developers.com/showthread.php?t=813309

How to root: http://forum.xda-developers.com/showpost.php?p=8896862&postcount=90

Kernel HZ value: HZ=500 is smoother, HZ=256 is Samsung default.


Memory configs (K10J and later):


THANKS: Big thanks to existz and xcaliburinhands for the i9000-to-i897 patch.


WARNING: If you use a custom boot animation, apps like One Click Lag Fix will not work because it disables the playlogos1 script hack.

The files with ending with -CWM are for flashing using Clockwork Recovery.
These other zip files are for flashing with ODIN.


The source code is posted on the GT-I9000 thread: http://forum.xda-developers.com/showthread.php?t=822756

>>> If you have questions, please read the FAQ: Frequently Asked Questions first!

>>> CLICK HERE to DOWNLOAD the kernels.


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Retired Recognized Developer
Sep 11, 2010
Hardcore - since you're one of the few still using universal lagfix, I have to ask if you've messed around with Steam at all? I have it booting perfectly on JPY, some issues with filesystem conversions, nothing major. Seems to work perfect on 2.2 ROMs so far.


Inactive Recognized Developer
Nov 9, 2008
Glad to see it come together hardcore! ... big thanks!...testing now

Im adding my Quick FAQ to the first page so everyone can see it....

(Some of this is taken from Hardcores FAQ...READ IT!)

[Q] What do all the tweaks in CWM mean? And which tweaks should I use?
[A] The speed tweaks in CWM is taking from Hardcores Startup Speed Tweaks here, http://forum.xda-developers.com/showthread.php?t=813309. You should use the first 4 tweaks, as the optional tweaks are only support for TUN and CIFS, if you dont know what they do then you do not need them.

[Q] After I flashed this kernel my screen does not rotate correctly..
[A] You have flashed the wrong version, there are 2 versions of this kernel, one for the Captivate and one for the i9000, the correct one will say i897 in the file name, make sure its there

[Q] After flashing this kernel, I have static, crackling..etc using bluetooth or during phone calls
[A] Chances are your using a Captivate modem, this is an i9000 kernel tweaked to work on the Captivate, so you need to use an i9000 modem, theres quite a few to choose from (JK3, JK4, JL2, JL3..etc) Theres a link in my sig, under the modem I use, where you can download

[Q] Im using JPY or another i9000 rom, do I need to flash the Captivate version or the i9000 version?
[A] You need to flash the Captivate version. This kernel is an i9000 kernel but the Captivate version is reoriented so it works correctly on the Captivate, the i9000 version is for the actual i9000

[Q] Do I need to disable lagfix coming from a previous version? (ie. K12K to K12L)
[A] No, you do not need to disable lagfix when switching to a newer version

[Q] I am currently using a Lagfix. Do I need to remove the lagfix before changing kernels?
[A] If you are using a loop lagfix like RyanZA's One Click Lagfix (OCLF), you *must* un-lagfix first. But if you are upgrading from another Universal Lagfix Kernel or Voodoo, you don't need to remove the lagfix. However, it is always safest to remove the lagfix before changing kernels.

[Q] Which lagfix do you recommend?
[A] I recommend EXT4 All lagfix, with the SAFER ext4 mount option. Other lagfixes have a high risk of data loss if the phone crashes or is suddenly powered off or rebooted

[Q] Whats the difference in the "warm" and "cold" versions?
[A] If you screen is to yellow, flash the cold version, it makes it more blue to even it out. If your screen is to blue, flash the warm version, it makes it more yellow to even it out.

[Q] Whats the difference between the 250HZ version and the 500HZ version?
[A] HZ is an internal timer value used by the Android/Linux kernel. It affects the timer granularity of some kernel functions. The higher the HZ, the smoother the User Interface should be, up to a certain point - too high a HZ value will make CPU-bound tasks slower. However, the differences are very minor.

[Q] When I try to go into recovery I now have 3e and says ..

[COLOR="Red"]Install from package
Finding update package
Opening update package
Verifying update package
E: failed to verify whole-file signature
E: signature verification failed

Applying Multi-CSC
Installing Multi-CSC
Installation aborted[/COLOR]
[A] Follow my guide here, takes about 2sec and your good to go.. http://forum.xda-developers.com/showthread.php?t=909213

Thats all that I can think of right now, if theres anything else that I forgot let me know and ill post it...
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Senior Member
Jun 26, 2008
Right when I thought I was set to flash a new kernel (Nandroid backup, Titanium backup, SMS backup, everything on SD ready to flash), you throw this at me... What to do what to do... >.<


Inactive Recognized Developer
Nov 9, 2008
I don't think you want to use this with your i9000 rom. This is a captivate kernel, use it with a captivate rom (Cognition)
This is a reoriented kernel...its actually based off of JPX 2.2.1, which is from the i9000...its just made to work on the Captivate...


Inactive Recognized Developer
Nov 9, 2008
Yea, I was actually just thinking that when I read the op for the 3rd time :) thanks for the possible red flag though, possibly saved me a head ache ;-)

Sent from my GT-I9000

You CAN run this with an i9000 rom, its built off of an i9000 kernel...just tweaked to work correctly on the captivate

Read the 1st post again, "Built from JPX sources"
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Senior Member
Nov 22, 2010
You CAN run this with an i9000 rom, its built off of an i9000 kernel...just tweaked to work correctly on the captivate

Read the 1st post again, "Built from JPX sources"
Thanks for clearing that up.

Edit: installed and testing.
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