XFX nForce 680i LT SLI - 3 builds - struggling

[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.

[srpeters18]

Blue means its getting power. Blue + amber means its got power and CMOS is at default. All three means its powered up and running.

[reneuend]

Thank you for the info. on the LEDs.

I tested the PSU (standalone) with a voltmeter and the connectors tested within an acceptable range. I'm guessing it's a short or a loose connection that I'm not finding.

I'm going to pull the board and put on the bare minimum. Add components in between tests.

Question: I read in another post that high-end memory sticks might cause this kind of problem. It was suggested to use a low-end memory stick first then up the voltage in the bios to accept the higher-end memory stick. What qualifies as high-end? I'm using OCZ Platinum Rev 2 2048MB PC6400 DDR2 800Mhz.

[foxmobouser]

I use OCZ plat rev2 and never had this issue from the start so i doubt its that

[srpeters18]

Actually, the OCZ plat is one of the brands notorious for requiring more than 1.8volts. Count yourself as lucky if you've never had that problem.

[reneuend]

If I want to get this board up and running, what type/size memory stick should I start with?

I'll have to pick it up on my way home from work today, because I plan on trying to get this board working tonight.

[Scott]

I would just pick up a sitck of DDR 2 667 or 5300. Somthing to let you get into the BIOS and up the voltage to 2.1V for RAM

[reneuend]

OK. I went to the local computer store and picked up a Buffalo 512mb pc2-5300 667mhz for $15. I'll report on how all this turns out after tonight.

Thanks for everyone's suggestions.

[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 :grin: ). Thanks for everyone's input.