XFX nividia 8600 GT 512..QE/CI as it wishes

There is some interesting issue with my card. QE and CI works sometimes only and not always. And you cant guess when it will work when it wont!..when it is not working then there is huge graphics/mouse lag/Freeze issues!. This sometimes happens even in safemode!

These are what i have tried.

Trail 1
Installed EFI string using EFI studio.
Result: Sometimes work, sometimes dont. Sleep will never wake. Most of the times after sleep. next reboot onwards, QE/CI gets disabled. Then only if it wishes, it will give QE/CI

Trail 2
Nvkush with and without EFI string
Result: Same as Trail 1

Trail 3
Tried Nvinject with EFi string and the with EFi string
result: No QE/CI all times..Sometimes, Mouse freeze and lags

Trail 4
NVdarwin
Result same as Trail 3.

Trail 5
Edited GEforce, natit, NVHDANV50, NVDresman.
Tried with EFI, W/O EFI, NVkush and different combos
Result: Same as Trail 1 on all variations.

Consistently
Sleep fails to wake up.
Enables QE and CI as it wishes

can somebody help.

Specs are as below
Mother Board A8N-VM (Not using Onboard graphics)
PCIe : XFX 8600 GT 512MB
Processor: AMD 64 Athlon 3000+
Kernel: voodoo
Distribution: Ideneb1.4 (10.5.6)

Onboard lan works perfectly. Audio in and Out working..but no volume control (Using 1986kext). USB working perfectly.(Legacy disabled).

Modifications
Seatbelt.kext to fix dmg issues

Kalyway 10.5.2 had no issues in terms of video. Was working properly even with sleep and Wake!