vasil_d and guys on thread http://www.arctablet.com/blog/forum/crewrktablets-rk3188-entwicklung-customroms-development-croms/request-4-4kk-rom-for-cube-u39gt-iconbit-thor-zx/ Has done some incredible job on tuning CUBE U39GT 1.04 release.

Read the whole thread and give guys some credit.

Here are the highlights.

1. Rom based on the 1.04 release.

2. Kernel from 1.06 released with stock CPU, GPU and slight overclock of the RAM. Thanks to PRIMUS for the mod. No over- or under- voltage. Just RAM to 600 Mhz and less stepping for CPU and GPU. Tested to be the best behaving kernel and best power usage.

3. PreRooted and SuperSU app for root access

4. Parameter file for 2GB space for user apps. I think we do not need more, because all large apps are able to be installed on SD

5. ! removed some lib .so files, because they contain trojan (ESET and Kaspersky confirmed)

6. Modded build.prop file for EN interface, removed ADB notification, faster scrolling and other minor stuff

7. Removed all china apps/crap

8. Edited some pictures for the rom

9. Minor stuff in adition

10. Last but important working TAKS/APP switching button. No need to go to HOME before switching to recent/other app.

Flash Using Rockchip Batch Tool v1.7 and RESTORE button!

Download from here:

https://drive.google.com/uc?export=download&id=0B4kmacwvOa1TZ25vZmFJYUhzLVk