kernelWhile CheckM8 has been around for a couple of weeks, it was just announced that it’s working 100% with the Sprint and Verizon CDMA editions of the HTC One M8, so I’m just now getting to it.

CheckM8 offers overclocking, Sweep2Sleep, Frandom support, exFAT support, disabled system write protection, Fsync, forced fast charge USB, F2FS support, added voltage control, and is compiled using the Linaro 4.9.1 toolchain.

For One M8 owners who were annoyed that their versions were clocked slower than the international versions, there’s a 2.5GHz “overclocked” board-spec version of the kernel, which behaves like the international versions do, as well as a 2.8GHz truly overclocked monster.

I tested out the 2.8GHz kernel, and the phone booted, 4G/LTE connected, and I discovered that 2.8GHz does not run well with my phone. It will boot and function fine until you put it under load, and then it reboots. Your phone on your carrier may be different. The crash didn’t hinder me from flashing the 2.5GHz board-spec kernel.

The CheckM8 kernel also seems to change the boot animation, or I’ve done something and not noticed it. I went from having a Harmon Kardon boot animation to a little logo that says “Android.” I could have just flashed something on the side that did that, though.

CheckM8 in action

The CheckM8 kernel is currently being distributed via Dropbox, which is a nice change from everyone using these hosting sites that have 40 fake download links that are advertisements and make you wait ten seconds.

As for performance on the 2.5GHz overclock, I went from 29K to 34K scores on AnTuTu. The ROM I’m running has been underperforming in the kernel side, and I’m not sure what was going on with that, but 33K AnTuTu scores are about where my phone normally is so this is about 3% faster right off the bat.

I’m not entirely sure how well this translates to real-world performance, but for a kernel that seems to cover all the devices, that’s a great start.

CheckM8 install

Take the usual precautions – have either a nandroid backup or a spare working stock kernel handy. This kernel seems to be pretty easy to deal with when it crashes a phone due to overclocking (or I crash it due to overclocking and blame the kernel), so minimal nandroid protection is needed.

If you install this and have some benchmarks to report, I’d love to hear them. I’m not sure if the ROM I’m using was responsible for the 29K scores with the H/K changes, or if the HK audio filter was ROM based or kernel. Basically I’d like to know if you get a 17% increase in speed, which is what I got at 2.5GHz on this ROM, or just a 3% which is what I suspect the case will be.

[xda-developers]