Member Avatar for DaMaGe

Please be patient because i am a newb !!

What ive got and the problem the problem:

A8N-SLI Deluxe Motherboard
XFX GEFORCE 6800 PCI-E 128MB DUAL DVI
Seagate Barracuda ST3200822AS 200Gb
AMD (Venice) Athlon 64 3500+
Corsair (TWINX1024-3200C2PT) 1024MB
350W PSU and 500W PSU

Well i have a complicated problem and in need of desperate help!!

It started to build a pc out of these components + all the extras. I plugged my 350W PSU into the motherboard and the and turned it on, it all booted up fine but i didnt get a display on my monitor, (newb guessing that the graphics card wasnt getting enough power so i replaced with a 500w PSU. When i switched it on, the motherboard didnt power on despite the green LED lighting up, no fans came on, which was the big indicator, i then swapped the back round just to check and make sure and yet the same thing happened.

Please can somebody help me because i am desperate to use this pc as it is a nice spec.

cheers

ps i have through the sticker at the top.

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As noted in the thread by and discussed by , the behaviour described is an inconsistent power/failure symptom rather than a simple display issue. The answers already offered focus on PSU capacity; the following condenses a non-repetitive, prioritized diagnostic path and a few checks that were not covered in the replies.

Start with a bench test (motherboard outside the case on a non-conductive surface) to rule out standoff/case shorts. Verify the board powers when the front-panel power-switch pins are shorted directly on the header (this isolates a bad case switch/wiring). Confirm the auxiliary CPU power connector (the 4‑pin/8‑pin 12V plug) is present and correctly seated — a correctly seated ATX main plug alone will sometimes light LEDs but not spin fans or start the rails that feed the CPU. Do a visual inspection for damaged components (burn marks, bulging/leaking capacitors) and try one memory stick in the manufacturer-recommended slot.

PSU verification: a paperclip test only proves a PSU will start idle — it does not prove the 12V rail will hold up under load. Use a multimeter or a dedicated PSU tester to check +5VSB is present before PS_ON is pulled low, then measure +12V/+5V/+3.3V while the unit is running. If a meter isn’t available, swap in a known-good, high-quality PSU (not just higher wattage) that has the correct auxiliary CPU connector. Record voltages or observable behaviour (fans, POST beeps) for each swap — that data isolates whether the fault follows the PSU or the motherboard.

Likely culprits in this kind of mixed behaviour are: a short/grounding problem on the bench/case, a failed PSU rail that collapses under load, or damaged motherboard power circuitry. If components are being returned, document the bench-test results (standby voltage, which connectors power fans, whether PS_ON behaves) so the vendor can reproduce the failure. Replace any suspect PSU before reusing other parts to avoid cascading damage.

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Member Avatar for djrivera1

The first I would do is pull out the XFX GEFORCE 6800 PCI-E 128MB DUAL DVI card, and throw in a old PCI card in to your PCI slot and see is it power up if it does it could be powersupply or video card is bad. If it doesn't you motherboard is Bad. (FROM THE SOULD OF IT YOU FRY THE MOTHERBOARD WHICH WHY YOUR LIGHT COME ON BUT NO FAN NOT A GOOD SIGN, SEEN THIS A FEW TIME CARD PROABLY WASN'T IN ALL THE WAY OR USE A 350 W POWERSUPPLY INSTEAD OF A TRUE POWER 480W OR HIGHER COULD HAVE DONE IT. YOUR COMPUTER TRY PULLING MORE POWER THEN IT COULD CAUSE THE VOLTAGE TO DROP AND THE AMPAGE TO JUMP WHICH WOULD CAUSE DAMAGE TO THE MOTHERBOARD.

1. Athlon 64 3500 89W
2.XFX GEFORCE 6800 PCI-E 128MB DUAL DVI between 77.5 Watts, and 123.5 Watts
3.A8N-SLI Deluxe Motherboard 75W
4.Seagate Barracuda ST3200822AS 200Gb
Power Management (watts)
Seek: 13.5
Read/Write: 13
Idle: 9
Standby: 2
5. DVD drive 12.5 w each
6.Corsair (TWINX1024-3200C2PT) 1024MB 10w
Total is between 302-336
Remeber a 350w not true power can only put out 275w or less. So I say go with a 480w Antec true power or higher.

Member Avatar for DaMaGe

But if i plug in my 350W PSU the motherboard is still booting up but with no display, but when i plug in my 500W PSU my motherboard doesnt boot up at all, the 350W PSU boots up but without a display.

Member Avatar for djrivera1

Look at the side of the 500w power supply read the ampage on each rail and post them 12v 5v 3.3v rail then you will have something that say 12+vdc 26A 5vdc 38A and etc. anything lower then the number on this post is bad, even thought it say 500w it no true 500w it might only be 285w and 500w peak. which is why the 350w might boot the system but no display but the 500w doesn't at all. if you didn't spend over $70 or higher on a power supply it no good spend the $159 on the antec 550w true power or the neo it true 550w not peak it, and also come with overload and inrush current protection and the 12v 5v 3.3v are complely different circuits. If this boot up system and no video I would reset the cmos if still doesn't work return videocard, but still keep the powersupply cheap powersupply burn up systems won't take a chance.

Member Avatar for DaMaGe

A bit unsure about what you have just said, i will read out the amps that i get on the power supply:

500w PSU

+3.3V - 30A
+5V - 40A
+12V - 20A
-5V - 0.5A
-12V - 1A
+5G sb - 2A
+3.3V & +5V MAX - 260W

So im a bit unsure about what your trying to say, i think im going to send back the motherboard as ive never got it to work, or should i buy a better PSU????


Sorry for being a dumbass

Member Avatar for djrivera1

Send back the Motherboard it proably bad, a better powersupply with 24pin atx ver2 will do since the 20A on the 12v rail is a bit low, get something with at less 26A or higher the 6800 nividia cards are know for draining a lot of power.

Member Avatar for DaMaGe

cheers for the help, already sent it back before your last reply

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