i5 661 ram compatibility issues

[cctay]

Hello, been building a new rig with half spares half new parts and i ran into some issues which i cant resolve as of yet. here are my specs

CPU : i5 661
MOBO: Asus P7P55D
HDD: WD 1TB Black
GPU : Sapphire hd6870
PSU: CM 500w
RAM: (problem area)

now the problem i'm facing is the ram. i have 3 setups,
A 1 stick 8gb 1600 kingston value ram;
B 2 stick 4gb 1600 kingston value ram and,
C 1 stick Mushkin 4gb 1333

i've updated the bios, tried everything in every ram slot, use memOK to underclock the ram. now the thing is with A and B, i can only get so far till windows loading screen and it crash and restart. I realised A is not supported with my MOBO therefore i went B, and it still crash.

with B either trying with 1 stick or 2 stick it still crashes. i tested both sticks in B in another rig seperated from this one and it works perfectly fine. so no ram defect here.

however, when i use C it loads perfectly fine into the home screen. so i'm confused here. what exactly is wrong? is it the ram? the mobo? or something else

thanks in advance for any responds!

 

[apache_lives]

rams golden rules:
1) least amount of modules
2) most matched modules

your also seeing early DDR3 memory controllers/devices with new DDR3 (8gb sticks, high speed memory etc) - its always going to be hit and miss

try setting the ram voltage to 1.55v and forcing it to 1066 or 1333mhz (correct spec from Intel - ignore the ASUS bs)

also take note crashing etc use memtest to confirm the memory is actually aok and not assume that not crashing means it fine

 

[cctay]

ok i'll try that now and see how it goes first!