Computer Tech Stumped... 680i SLI Reboots

[dawgrum]

Ok, I had customer bring in some parts he ordered off of Tiger Direct. XFX Nforce 680i, Core 2 Quad, and 2 gigs of Corsair DDR2 800. I build everything, get to windows install screen... reboot. I pull out the ram, reseat it, try again and success, it installs windows. I boot windows up get some of the drivers in, it reboots. I try it again, it reboots as soon as windows loads. I try it again and now it won't even load windows.

My next step is replacing the ram with some DDR2 667 I had. It boots up and reboots instantly. I try it again and it stays on. I install the rest of the drivers, games, updates, ect, and it never reboots. I had it up for 24 hours with no reboots, so I figured, problem solved... bad ram.

I order him new All Components DDR2 800 and send him home with his comp and the DDR2 667, a loaner if you will. The DDR2 800 comes in, he picks it up and installs it and now his computer starts crashing again... he brings it back, I put in different DDR2 667, and its stable.

My question is... what is going on haha. Does anyone have any advice on why it wont take DDR2 800? I tried putting the voltage to 2.4 but it wouldn't boot. I don't have very much experience in changing the timing of RAM so hopefully I don't have to go there. Any advice is appriciated.

[xfxsupport]

If you disable SLI memory in the BIOS does that help? Are you using 2 sticks to get 2 gigs or 4 sticks or RAM? What are the exact details on the RAM so we can check on the voltages and timings for you.

[dawgrum]

I checked the SLI memory under Advanced Chipset Features, and it was "not detected". As for the RAM, I am using two sticks of "All Components 2GB DDR2-800 CL5".

Hope this helps, also, if this RAM isn't a good fit for the board, any suggestions?

[srpeters18]

Try timings of 5-5-5-15 and set the command rate to 2T. Most memory runs at 2T when you've got 4GB.