With Corsair HX520 computer wont post

[tendril]

Hi there

My new machine:

Asus P5K-E WiFi Intel P35 (Socket 775) PCI-Express DDR2 Motherboard
Seagate Barracuda 7200.11 320GB SATA-II 16MB Cache - OEM (ST3320613AS)
Corsair 4GB DDR2 XMS2 PC2-6400C5 TwinX (2x2GB)
Antec Nine Hundred Ultimate Gaming Case
Corsair HX 520W ATX2.2 Modular SLI Compliant PSU (CMPSU-520HXUK)
Gainward ATI Radeon HD 4870 512MB GDDR5 TV-Out/Dual DVI/HDMI (PCI-Express)
Intel Core 2 Duo E8500 LGA775 'Wolfdale' 3.16GHz (1333FSB)

Wont boot with the HX520 inside it - the fans do power up and all the lights come on but nothing on screen. The beep warning from a speaker I attached tells me it cant detect VGA. So I googled and saw someone mentioning a faulty psu being the problem. I replaced the PSU with an old 400w spare I had and it boots fine!

In both cases I definately had both cables attached to the motherboard and both pcie 6 pins attached to the graphics card. I have doube and triple checked this. After booting with the old psu i put the HX520 back in but no luck still.

I have emailed support both at the supplier (overclockers.co.uk) and Corsair but if anyone here can provide some ideas I would appreciate it a lot!

Thanks

[LuckyNV]

might sound obvious but did you plug in the +12V power cable, I think your mobo can support 8pins, its near the CPU socket.
If its got a cap on it, remove it and plug in the 8pin cable (should be labelled as EPS+12V)

[tendril]

Originally Posted by LuckyNV

might sound obvious but did you plug in the +12V power cable, I think your mobo can support 8pins, its near the CPU socket.
If its got a cap on it, remove it and plug in the 8pin cable (should be labelled as EPS+12V)

hi there - thanks for the reply

yeh I made double sure that I had both that 8pin cable and the main (24 pin?) cable plugged into the motherboard. I did the same with my 400w spare PSU and it booted fine.

[Yellowbeard]

Unfortunately, it does sound like a bad PSU. You can try this troubleshooting step if you like: http://www.houseofhelp.com/forums/sh...ad.php?t=63991

[tendril]

Originally Posted by Yellowbeard

Unfortunately, it does sound like a bad PSU. You can try this troubleshooting step if you like: *link*

Hiya

Thats a shame - guess I shall have to return it. It seems I must be very unlucky as I have heard only good things about this PSU! Hopefully the replacement will work ok.

Thanks for the link - I read that earlier today. When I powered the machine up the fans did switch on etc so it would seem to be the case that it is partly faulty in that it can send power to the machine but not enough to juice everything properly...