My motherboard will not recognize dual channel for some reason. Here are my specs :

EVGA 680i TR Mobo
2 sticks 512 PNY DDR2 667
2 sticks GSkill DDR2 667
EVGA 8800GTS 320
Ultra X3 600w PSU
74gig Raptro
160gig IDE
Pentium D 820 2.8ghz

I know the ram is cheap, but it did come with heatsinks. Tried just 2 sticks, it wouldn't recognize dual channel, tried all four, still wouldn't recognize. I am using the right slots too. Bios are updated. PSU works fine. Tried with an overlclock, tried without overclock. Any suggestions??

if you put them in the right slots as you say you did, then only 3 things it can be..

1. dual channel disabled in bios (if possible)
2. your mixing different types of ram (some mobo's require matched pairs in all slots occupied)
3. mobo bad.

See if you ram runs in dual channel just with the same manufacturers. Like run pny by itself then your g skilll; also upgrade your cpu.

Maybe the ram isn't dual channel ram?

put tthe pny in slot 1 and 3 and the gskill in 2 and 4

Are you saying the BIOS doesn't recongnize the memory? What are your simptoms? Are you saying you changed the ram voltage?