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Hi,

Firstly, I have read the FAQ.

My problem:
I installed new pair of Kingston 8GB DDR3 1600 kit (2 pcs.) ( Datasheet for it )
on my Asus P6T Deluxe mobo with i7 920 processor.

Before upgrading I have not had any problems at all and now my computer will not power up at all. The fans don't spin up, only the mobo power switch and reset buttons are blinking with fast pace like flickering.

Nothing else was touched during the install. I have tried reseting the CMOS by taking out the battery for few minutes.

Oh and I have also tried to change the old RAM back and the problem stays.

Thanks.

Edited by Mudi- because: fixed tittle
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Good outcome: replacing the PSU fixed it. That is the important takeaway for anyone reading this later. The symptom set here — case LEDs or front-panel lights alive while no fans spin and the board produces no POST/beeps, and resetting CMOS/re‑installing the old RAM had no effect — is classic for a PSU whose standby rail is working but the main rails are not delivering power. confirmed the PSU swap restored normal operation, so the RAM upgrade was coincident with a power-supply failure rather than the root cause.

Short, safe diagnostic checklist (use before buying a new PSU)

  • Power down and unplug AC. Remove drives, optical devices and discrete GPU, leave only motherboard, CPU (and cooler) and PSU connected.
  • Reconnect ATX 24-pin and CPU 4/8-pin (EPS) power. Try to power on. If fans still do not spin, the PSU is suspect.
  • If available, swap in a known-good PSU or use a commercial PSU tester / digital multimeter to check the +12V and +5V rails. A paperclip jump-start is a last resort and not a substitute for proper testing.
  • If the PSU tests OK, try the minimal-beep test (no RAM installed) to confirm the board posts; also check front-panel power-switch wiring and for motherboard shorts (standoffs, stray screws, bulging caps).

Notes on replacement and prevention: choose a reputable PSU with enough wattage for your system and 80+ efficiency rating, and confirm it has the required 8-pin CPU and any PCIe connectors. Keep the old PSU (if safely possible) for bench testing later, or borrow a known-good unit to verify before discarding. After replacing the PSU, run a memory stability test (MemTest86) to confirm the new RAM is actually compatible and stable under load. Safety: if you are not comfortable probing voltages or opening the PSU, get a technician to help.

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When you mean fan, do you refer to fan on motherboard or power supply fan?

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Just checked this and none of the fans start to spin. Including power supply fan. Yet there's a flickering light on the power and reset buttons.

Edited by Mudi- because: n/a
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If none of the fans worked, turn them off immediately. You don't want your computer be toast because of stupid overheating.

Have you checked all the cable from power supply to your motherboard? There are 2 main cable to take note, the 24pin (large one) and 4pin (yellow and black cable) and make sure both of it connected properly to the motherboard. If still none, unplug it and plug it back afterwards.

Member Avatar for Mudi-

I have now checked that every cable is connected properly on both ends and there is no change, fans will not power up, yet the lights flicker. Tried to unplug and plug them back in and nothing happened.

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Ok lets troubleshoot a little..

First unplug all cable connected to your motherboard, power supply, HDD, SATA cable and DVD-Rom and even RAM. (except cable from your casing)

Then plug in only power supply cable to your motherboard (2 cables) and turn on your computer. If it beeping about three times plus all fans working, then put back RAM and see if the beep still there and observe the fan as well.

Member Avatar for Mudi-

Still the same situation. Only flickering lights. No sound.

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Then it's your power supply problem. It only have enough power to light up LED but not the motherboard itself. Consider buying new power supply for your desktop or if you have old computer or other computer that you use, try to salvage it for a while and try it on the faulty computer. If it's on, then most likely your power supply is dead.

commented: Solved my problem! :) +1
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Going to try it out. Thank you for you help!

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Just wanted to tell you that it was infact the PSU that died. Got a new one and everything is working great! Thanks alot!

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