Computer wont power up, second opinion needed

blainj2

My computer wont power up at all at the minute. Below if a bit of background on what happened to get to this point and the computer spec which i built myself with help from this forum.

• Installed new SW from USB stick
• The next day when i push the power button nothing happened
• I unplugged everything and reconnected it and it started
• Went away for weekend left computer unplugged
• Came back and turned computer on and the power light just flashed on and off and i could hear the fans turning inside
• Looked into what it could be and came across something about USB a possible USB short
• Looked into USB port where i was using USB stick in and the pins were all bent and touching metal on otherside
• Disconnect power and straighten pins, reconnect everything and try again. now i get nothing, no flashing lights no fans turning
• Its the front USB panel so i disconnect it from motherboard and try again still nothing
• Test power supply with multimeter and everything is working correctly
• Check power switch pins on motherboard and these are getting power, pressing switch or crossing pins doesn't do anything.
• Disconnect everything from motherboard apart from CPU still nothing, no beeps

Computer Specs

Item Price
Microsoft Windows 7 Home Premium 64-Bit (SB-Version)
8GB-Kit Corsair Vengeance DDR3 1600 MHz CL9
Seagate Barracuda 7200 2000GB, SATA 6Gb/s
Gigabyte GeForce GTX 660Ti OC, 2GB GDDR5, 2x DVI, HDMI, DisplayPort
Samsung SH-224BB bare schwarz
LogiLink Wireless LAN 300 Mbps PCI Karte 802.11n 2T2R
be quiet! Pure Power L8 CM
Corsair Carbide Series 500R White, ATX, ohne Netzteil
Samsung SSD 840 250GB SATA 6Gb/s
Thermalright HR-02 Macho Rev.A (BW)
Intel Core i5-3570K Box, LGA1155
ASRock Z77 Pro4, Sockel 1155, ATX

Computer had been working perfectly up to this point for a few months btw.
Any other trouble shooting i can do to definitely identify the problem?
I though the motherboard was protected from a USB port short?

The Glass Key

Bent and shorting out USB pins will cause the issue you have, but normally if you stop them shorting out everything works OK again. The examples I have seen have just caused the PSU to cut out until the short is removed.

Well worth trying another PSU.

blainj2

You have given me an idea, maybe when i tried the usb stick in one of the back USB ports i bent a pin there too. This could be an easy fix, fingers crossed. It was one of them new micro USB sticks with no real outer casing and i was plugging it into USB 3 ports, that's how they got bent.

Does anyone know why the motherboard would do the flashing power LED and fans turning? This might help me get to the bottom of it.

The Glass Key

A couple of googles and a quick test (shorted out some USB pins on an old system that I was given that originally because it had a short on one of the USB connectors on the front panel) gives a result that a flashing LED can be caused by shorted out USB pins. When I plugged in the known bad USB front panel and then switched on and the internal LED flashed, no short and its on all the time.

blainj2

I think my motherboard might be dead?

I took it out to have a look but can't see any burn sport or anything like that. USB ports at the back are fine.

Any ideas? Should I just send the mobo back?

The Glass Key

You can't really send it back until you have tried another PSU, if on return they test it and find its working then its just a waste of time for everybody.

blainj2

Pity I don't have one lying about to double check. I have tested all the pins on my existing one when it's turned on (using paper clip) and they are all at the correct voltages.

It's a pity this mobo doesn't have a built in led that might indicate a fault sequence or something.

The Glass Key

blainj2 wrote: »

Pity I don't have one lying about to double check. I have tested all the pins on my existing one when it's turned on (using paper clip) and they are all at the correct voltages.

It's a pity this mobo doesn't have a built in led that might indicate a fault sequence or something.

Only problem is that you have tested the PSU in a no load situation, sometimes the voltage will drop as soon as you put a load on it.

I've seen some totally unexplainable issues with PSU's so would always try another just in case.

Pappacharlie

Is there a green light on your display? Is it getting a signal from the PC?

blainj2

I tested the psu in another computer and is working fine. Also tested another psu with my motherboard and got nothing. Seems like it is my motherboard. Could it just be a fuse or something simple blown?

I've contacted hwvs about returning it but they haven't got back to me yet.

The Glass Key

I've worked with specific motherboards on commercial projects and got to know the boards inside out for troubleshooting and I've never been able to fix a blown one. Modify, yes (like changing the boards tolerance to poor quality power supplies) but repair once dead, no. If you did try replacing anything on the board you'd be voiding the guarantee so your only option is a replacement.

blainj2

Just to close this off. I sent the motherboard back to hwvs using their online return process. Printed the label off and left it back to UPS on Monday the 14th. If arrived in at hwvs ont he 18th.

They were very hard to get updates from by email or phone and i was starting to get worried when a replacement motherboard arrived yesterday (29th). I put in back in the computer and connected everything up all was good again.

Didnt cost me anything in postage just a bit frustrating that they didn't let me know what was happening. At one stage they told me they had refunded money back into my bank account!

Baked.noodle

Just to say my brother shorted a USB port by plugging in the header into the motherboard incorrectly, and fried his motherboard. I assume shorting USB is fatal more often than not.

smacl

The Glass Key wrote: »

I've worked with specific motherboards on commercial projects and got to know the boards inside out for troubleshooting and I've never been able to fix a blown one. Modify, yes (like changing the boards tolerance to poor quality power supplies) but repair once dead, no. If you did try replacing anything on the board you'd be voiding the guarantee so your only option is a replacement.

Fixed a couple of Dell boards recently that got too hot and blew out some of the larger electrolytic capacitors. Ugly repair job mind you, as I couldn't get the solder sucker to work on these boards so it was a snip and wire job. Wouldn't normally bother tbh, replacements are cheap enough.