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Power outage then no post, new MOBO, RAM, CPU now no power at all Please help.

HI, I was sitting working at my desk and we had a storm Thursday and the power went out. Has happened dozens of times. I have had the current computer I was using for four years. I use it everyday for work, Avid Media Composer, photoshop, after affects etc... I built it in 2010.

After the power returned the computer would turn on, the fans would spin the light on the mother board was on but no post.

The specs on that computer were:

Windows 7 pro 64
Asus p6t deluxe v2
Corsair ddr3 1600 6x2 ram
Intel core i7 920 cpu
corsair 750w psu
NVidia quadro fx1800

So because I need to fix this quickly I read as much as I could and assumed my mobo was dead. I went to frys and talked it over, was not pressured, and decided to buy a new mobo, cpu and ram

I ended up buying:

Asus z97 mark 2 sabertooth mobo
Intel core i7 4790k cpu
Patriot ddr 3 2400 MHz 2x8 gb ram

then took everything apart, backed up my boot drive knowing I have to reinstall everything and put it all together.

oh and I have a blue ray drive, a sata boot drive, and two raidO's consisting of 4 1tb drives each.

so I put it all together plugged it in and hit the power button and nothing is happening now. the green light is on the mobo but nothing happens. When I first press power the fans spin about a quarter of the way then stop. I opened it up and made sure all the power cables were seated correctly.

So I am stumped here. In the morning I am going to buy a new power supply. My big question is did I not need to buy anything but a psu? is it possible the gpu is blown? Could my mobo and gpu been blown?

any help would be appreciated I need to get this up and running and get back to work like yesterday.
9 answers Last reply Best Answer
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  1. Best answer
    With a power surge - it is almost impossible to determine if one, two or all of the components have been fried. I have 5 computers at home, and I keep a spare PSU around and I "breadboard" the computer (take everything out of the case, assemble on a table top hooked to my known good PSU). In breadboarding, you only want 1 RAM stick, use the onboard graphics if you have it - no drives hooked up. It is a basic test of the mobo & CPU.

    If it posts - try the old PSU. Next, you add the other RAM in. If you are still good, add the GPU. If all is good there, add the boot drive and try to boot. If all passes, re-install everything and give it a shot again.
  2. The component that is most likely to fail due to a surge or other power line issue is the power supply.

    My guess is you changed nearly everything except the component that is actually defective.
  3. I am afraid I did the same. Gulp. 700 dollars later its the power supply.

    I am going to buy a new corsair hx850 psu in the morning and hook everything up again.

    is it weird that the fans were spinning though? doesn't that mean the psu was working? That Is why I thought it was the mobo.
  4. Theebs said:
    is it weird that the fans were spinning though? doesn't that mean the psu was working? That Is why I thought it was the mobo.

    If you have a multimeter, measure voltages across all output rails and the PWR_GOOD pin on the ATX connector.

    One possibility is that the PSU does not assert PWR_GOOD so the motherboard stays in continuous reset or PWR_GOOD de-asserts soon after getting asserted so the system gets reset before having a chance to do anything.
  5. The PSU can be damaged and not outputting the correct voltage/wattage to power up everything - and the fans may spin. I would suggest breadboarding your old system with the new PSU first, if it is dead, put the PSU in the case and see if the new stuff works.....

    Also - make sure you follow the checklist - http://www.tomshardware.com/forum/261145-31-perform-steps-posting-post-boot-video-problems
  6. Hi, so I picked up a thermal take 850w power supply and put it in with all the new components. Powered right up and went to post.

    Took everything out and put the old stuff back in exactly as it was. It went back to doing what it was originally doing. Fans spin, light on the mobo but no post and this time the hd led was just solid and it was basically hung. So I am going to assume the psu died and took the mobo with it.

    I guess I will just put the new stuff back in and reinstall everything. This power outage cost me 900 bucks and lost work time. What a bummer.
  7. On the bright side:
    1- you did not buy those other components for nothing
    2- your old PSU did not fry your new components
  8. I didn't realize the old pus could have ruined the new components. Got lucky there I guess.

    Everything is running, reinstalled windows and it recognized my four drives as two raids with everything intact which is fantastic.

    My gripe now is that my avid keyboard is ps/2 and there is no ps/2 input on the board. Wish they would leave those on there. Been to frys twice today and both adaptors have not worked, will not find drivers. So I am going to go one more time and try the last one they have.

    Then the real issue of reinstalling avid media composer. That won't be fun.

    Thanks for the help guys, much appreciated
  9. Electrical surges theoretically should be stopped by a good surge suppressor and/or battery backup unit. This doesn't always work - remember that your network cables can carry current, USB devices and basically anything else that is plugged into the computer. I had a friend that had a surge over surveillance equipment plugged in via USB. Fried the mobo, but the power supply, surge suppressor and a few other components were ok. The CPU and RAM were old, so we replaced them with new equipment (she wanted to upgrade).

    You never know what gets fried and what doesn't. You might want to look at a surge suppressor replacement. You might want to verify that your cable TV and telephone cabling is properly grounded and protected as well.....
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