Member Avatar for FishB8

I have now gone through 4 motherboards. Something about my rackmount case is cooking them! Help!!


When I assemble the bare bones systems outside the case, everything is peachy. It boots up, shuts down, posts, I can fiddle with the BIOS, etc.

As soon as I sick it in the case, and try to boot it up, the CPU fan spins a couple times and then everything goes dead. No post. I take the motherboard back out of the case but that doesn't change anything. Parts of the mobo still seems to function when the power is on. Ethernet lights blink a couple times when I plug a cable in. The green light on the ASUS board comes on, but when I try to power up, nothing. I've tried several different boards that are different makes and models. Same problem.

I've been trying to find out what is wrong, but each time I try something different and it doesn't work, I have to slap down another $200 for a new motherboard.

I find it hard to believe that a simple grounding problem would totally render the motherboard useless. Most people who talk of grounding problems usually say it works again once they remove it from the case. I also thought it might be a problem with the swap-bay back plane, but it's already been replaced once.

I've already ordered a new case, but has anybody ever heard of something like this? This is a totally new problem for me, and if the new case doesn't fix the problem I'm throwing the stupid thing in the lake!!

Are these boards a total loss? Is there anyway to revive them? What exactly is getting fried? I'm wondering if maybe an electrical current is clearing the ROM somehow. Would ordering a new ROM fix this?

This isn't much to go on, but given I cook the motherboard every time I try to figure out what is going on, I don't know much either!

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Dani AI

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This expands on the suggestions by , and with a short, ordered diagnostic routine and safe meter checks to isolate case vs. PSU vs. motherboard damage.

Start with a clean bench test (isolate the chassis)

  • Put the board on a non‑conductive surface (cardboard or wood — never the conductive side of an antistatic bag). Fit only CPU+cooler, one stick RAM, PSU and video (if no onboard VGA). Leave all case cables, front‑panel headers and drive backplanes disconnected.
  • If it POSTs outside the case, the next step is to recreate the failure by mounting the board in the chassis on an insulating spacer (cardboard sheet) — if it fails only when touching the chassis, it’s a short/contact issue. If it fails even on the bench after being in the case once, assume there may be permanent component damage.

Basic PSU / meter checks (safe, practical)

  • With PSU unplugged, visually inspect the board underside for scratches, loose screws, extra standoffs or solder blobs. Remove any extra metal standoffs.
  • To test the PSU: disconnect it from the board, short PS_ON (green) to any GND (black) to start it, then measure between each rail and ground:
    • +12V (yellow) ≈ 11.4–12.6V
    • +5V (red) ≈ 4.75–5.25V
    • +3.3V (orange) ≈ 3.135–3.465V
  • If rails are OK with the PSU unloaded but collapse or the supply trips when the motherboard is connected, the board is presenting a heavy short. With the PSU removed, a continuity check between each power pin and ground that beeps (near 0 Ω) suggests a hard short — note that some caps show low resistance, so use judgement (very low ohms is bad).

What usually fails and next steps

  • Repeated shorting typically damages VRM components, MOSFETs, caps or the flash ROM. ROM can sometimes be reprogrammed/replaced, but hardware damage requires component repair or a replacement board.
  • Try a different, known‑good PSU and the insulating spacer test inside the case. If the chassis is the culprit, look for misplaced risers, I/O‑shield contact, or a stray screw/wire touching traces.
  • For stubborn shorts, use a current‑limiting lamp/dim‑bulb tester or a qualified electronics shop rather than repeatedly powering the board.

Safety note: if uncomfortable with mains or PSU testing, get a local tech to avoid injury or further damage.

Recommended Answers

All 5 Replies

Member Avatar for jbennet

Are you putting the standoffs in!!!!????

The motherboard should not touch the case. There should be risers for the screws that lift it slightly off the bottom of the case

Member Avatar for jaymz1972

Same thought here Jbennet. Or maybe one of the risers in the case is touching the MB incorrectly resulting a short circuit.

Member Avatar for madoverclocker

are you using the same psu? if there is a different psu in the case, that could be your problem.

Member Avatar for cguan_77

when you place your mobo on the casing don't power it on, check the + supply of the mobo through the atx conn if it's shorted to the ground, if it is not shorted then it could be your psu is the culprit...

Member Avatar for FishB8

The PSU has been the same. It's a Thermaltake W0131RU 850W.

: yes, I'm using the standoffs. Although they aren't brass ones like I've usually seen.

: How would I go about checking for the grounding problem you described? I have a meter, but I'm not sure exactly what points to measure from, and for that matter what is considered "normal" and what is not.

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