nForce 680i LT SLI - no response

[reneuend]

Motherboard: XFX nForce 680i LT SLI
CPU: Intel Pentium D 925 3Ghz DT 800FSB Socket 775,Presler, Dual-Core
Memory: OCZ Platinum Rev 2 2048MB PC6400 DDR2 800Mhz ( 2x10 )
Video: NVIDIA GeForce 8500 GT 512MB PCIe 128 bit
HDD: Western Digital 250gb WD Cavlar SE (WD2500JB)
CD/DVD: Samsung 20x lightscribe dvd burner

I originally used a wrong ATX PSU (20 pin, 4 pin). When I tried it, I had all 3 leds light up and the fans worked, but it wouldn't boot up.

I've since bought an Ultra LS 500 Watt (24 pin, 8 pin). After I reinstalled all the cables, only the blue LED and amber LED are lit when PSU is powered. When I depress the power button on the case, the front panel case leds flicker then nothing. No fans, no response. The MB LEDs remain the same (blue and amber). I've checked all my connections. I don't see anywhere in my manual what the MB LEDs represent. The green LED is not lit up. Is that significant? What steps should I take to resolve this?

Thanks for any assistance.

BTW, I have 3 of these to build for my kids. All are the same configuration.

:frown:

[reneuend]

I tested the PSU (by itself) with a voltmeter and all the connectors are supplying the voltage within the acceptable range. That rules out the PSU being the problem.

Because the original PSU at least started up the fans, I'm guessing the board is shorting out or there is a loose connection that I'm not finding.

Based on what I've read in other posts, I'm going to pull the board and put only the minimum necessary to get it started.

Someone mentioned in another post that it may be necessary to change out the memory sticks with something low-end. Then change the bios to a high voltage to accept a higher-end memory stick. Question: What is considered higher-end?

I'll return with my results tomorrow night.

[reneuend]

I bought a low-end RAM, connected all cables, started the machine, entered BIOS, changed the memory setting from the default 1.8v to 2.1v. Saved and turned off the computer. Then I replaced the RAM with the 2 high-end RAMs and restarted. All has been working well and my daughter received her machine today, her birthday. My two boys machines went the same way. No problems and everyone is happy (including me :lol: ). Thanks for everyone's input.