OK so i just built a new computer, the Motherboard is a DFI Lan Party DK P45-T2RS PLUS, I got 8 gigs of OCZ reaper DDR2 1066.

Installed everything got the computer running fine on vista64, ran Memtest86 and got errors, I figured there was a bad dimm or something so i took 3 of the modules out and tested each 1 by 1 each had errors...so this leads me to thinking its something with the motherboard/bios...

I have no idea how timing and stuff works but right now this is what the settings for the RAM look like in BIOS

DRAM Speed 400/800
Target Speed 800
now for timing...
tCL:5
tRCD:5
tRP: 5
tRAS: 15

and the 7 other things i see in the timing part are all set to auto...i did enter the 5 5 5 15 on my own because i read something about it helping but i feel like i have messed something up and im honestly not really sure what im doing.

thanks so much

M3deman, what is the model number of the OCZ Reapers? I looked at their website and I suspect that you are using timings from an EPP profile. With the model number, we can look up the specified timings and voltages at OCZ.

Also, get a copy of CPU-Z to read the JEDEC profiles out of SPD for the DIMMs. This will let you see the timings and voltages that are programmed into the DIMMs. You should try running a standard profile before trying the enhanced (EPP) profiles. Run MemTest86+ with each valid profile and see which works best.