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System not power up, cpu fan is running [Solved/Closed]

rajan - Latest answer on Dec 27, 2012 03:39AM
yesterday my PC shuts down automatically and it fails to power up, but the smps & processor fan is running, no other LEDs, no signal nothing. what will be the cause... how can I handle this prob..?
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moins plus
Had the same problem with an HP Pavilion PC. Called tech support and they resolved the issue. They had me unplug everything to the machine, including the power cable. Then, I had to hold down the power button for 30 seconds. Apparently, this drains all power that is stored and rests something. I thought the guy was just following his checklist, but you can imagine how surprised I was when my computer booted up.

ErIN- Jul 1, 2010 04:36PM
same here , it doesnt to the trick and my fans are still onn heres what happens
1.everythings off
2.pressed power button
3.when com. turns on the fans aytomatically start to run
4. when I go to turn on the monitor, it says "no connection detected"
5. and the monitor immediatly go to STANDBY
but the fans are still running and power button is on too
What do?
JoeBlo- Aug 12, 2010 09:33PM
Thank you sooo much KevDMD, worked like a charm
Neecie- May 1, 2011 08:33PM
I had the same problem with mt HP pc and the 30 sec trick worked!!! Cleared all of the dust, cut the power, and held down the power button for 30 seconds and now I'm up and running again! Thank you, thank you, thank you!!!
RanNel- Jul 7, 2011 07:02PM
Yeah! I have a Gateway and this fix worked for me. Thanks :)
kajsjw- Dec 27, 2012 03:39AM
My computer won't turn on but the fan is running and my CPU is lighting up
moins plus
I had this exact problem yesterday where the CPU fan came on like a jet engine and the PC didn't start and the monmitor was blank. I simply opened the case, blew out ALL the dust bunnies, in the case and on all the boards and heatsink, fans etc, reseated all the power supply cables/connectors, especially the main pcb fan and 20 pin connector on the main pcb. When I plugged it back in, everything was fine. Yay!

Just clean all the dust from the heatsinks and reseat all the connectors. I did not fool around with the cpu or thermal paste etc.


moins plus
I had the same problem with my old Dell and a new desktop. I think it was the problem with Tuneup Utilities program. In my old Dell, I removed the battery from motherboard. It worked!

For my new desktop, I noticed the fans running were not CPU fans. They were the side and back fan. Actually, the CPU fan was off. It did not turn on when I tried to restart the system from sleep mode. I did the following:
1) unplug all cables
2) unplug CPU fan wire from the motherboard
3) plug CPU fan wire again
4) Turn it on and the side and back fans turn back to normal

moins plus
Worked!!! Thought it was motherboard, happened once before and I had motherboard replaced. Thank you! 30 seconds and all better now.

moins plus
Thank you KEVDMD (above) for your thoughtful consideration in writing your post.

I was installing new memory (in Gateway PC) and thought the computer was shut down when it was actually in hibernation mode. I shut down when I was done and couldn't boot back up. Fan's were running and power was on, but nothing else.

Based on a few Google searches and subsequent forum discussions I came to the conclusion that I needed to reset the motherboard/bios via the pull battery method.

UNTIL I read kevdmd's post above.

Instead, I decided to pull the power chord in the back and drain all juice to the motherboard. After, I booted up and heard 3 beeps. Now i'm getting somewhere! I shut down again and ...VOILA! I couldn't be happier to hear Vista's startup theme!

Hope this helps anyone else with the same issue.


moins plus
hay I am also face same problem dont know what to do my brain memory is hang I need flash on my brain lol

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