DarthJabba said
if you run the RKAndroidTool, it should see the tablet, and you will easily be able to flash with it a safe kernel (e.g., the stock one, or T14) - just make sure that the bootloader and the parameter file are ticked, and that the right kernel image is selected (and the kernel is also ticked).

Are you sure that flashing bootloader and parameter files are neccessary? When I was flashing your first OC kernel over custom beta1, I just marked a new kernel to be flashed and everything went ok...?

Wintermute said
Just stopping by to report a successful flashing of top clocked T15 kernel on my 4.4.2 "custom beta 2". Have managed to flash it using RKAndroid just fine.

Have you flashed only the kernel, or bootloader and parameter files too? Also can you give the exact link for custom beta2, because I have at least 3 beta2's which claim they are beta2, so now I don't even know what is what I might give it a second try with T15@720Mhz. If it doesn't work again, I might flash your beta2 and try with it.

OK, I gave it another try, but this time with power cable connected and fully charged. No luch either. Even worse. After first restart (after kernel flashing) it got into bootloop, but after 3-4 tries, it managed to reboot into recovery mode. But after second reboot - black screen and no signs of life. I revived it using RKAndroidTool. I also tried to flash the kernel from there (without parameter/bootloader), but this time it was stuck on first Cube logo and not doing anything. So now I have 1.8@stockDDR again. At least it's booting I'll call it a day, untill DarthJabba cooks something else

DarthJabba said
I am using the original Kasty 4.4.2 (i.e., the one without the multi-user stuff). Is this what everyone else is using?

I'm using the rom posted in 1st post of this thread.

DarthJabba said
PS: I will upload later the T15 kernel with stock DDR, just to eliminate the possibility that the reduced voltages is not the real problem. At the moment, we are assuming that the problem is with the overclocked DDR - but we need to ascertain that this is truly the case.

OK, I'll test it as soon as you upload it. But could you simply up the DDR voltage a bit (for 720Mhz), or loosen the timings or something? Ofcourse if you found their offsets in .img file too...

DarthJabba said
Ok, perhaps the problem is with T15.

I wouldn't say so, at least on my end. I tried all of your 8 new kernels and only the ones with DDR set to 720Mhz (T14's) keep failing. Here are my results:

1) kernel_305kitkat_cpu1800_t14_gpu768h_ddr460 ok
2) kernel_305kitkat_cpu1800_t14_gpu768h_ddr600 ok
3) kernel_305kitkat_cpu1800_t14_gpu768h_ddr667 ok
4) kernel_305kitkat_cpu1800_t14_gpu768h_ddr720 reboot after sleep
5) kernel_305kitkat_cpu1800_t14_gpu768h_ddr720_ex bootloop
6) kernel-305kitkat_cpu1800_t15_gpu768_t15_ddrstock ok
7) kernel-305kitkat_cpu1800_t15_gpu768h_ddrstock ok
8) kernel-305kitkat_cpu1800_t15_gpustock_ddrstock ok

4th kernel is very promising, because it's very stable at everything I throw on it, but when the screen goes off (when tablet goes to sleep), is always reboots instantly. So it could be that the voltage for standby frequency is set a bit too low? Could you try increasing it a bit, so I can test that too?

Now I'm on 3rd kernel which gives me score of ~20600 in AnTuTu (highest among 5 consecutive tests). That's about the maximum I saw on my tablet, so I'm very happy with it. The UI is much better, but still not as in 4.2. It could be due to many many apps that I've installed, so it could be just me.

BTW, what is the difference between 4th & 5th kernel, and 6th & 7th kernel? And what is the core difference between T14 and T15? Could you apply T14's frequency table to T15? I think T15 just needs some fine tuning.

That's all from me for now. If I can be of any more help, just say the word.