Computer wont start but light on mobo

[Jockbh0y]

So i was gaming away fine the other day and shut down the computer as normal.

Came in from work yesterday and hit the power button but theres just nothing.

I've opened the case and there is a green light on the mobo, so does that mean it cant be the psu?

Theres absolutely nothing on, no fans or anything, just the green light.

• Intel Skulltrail, i5400 Express 771x2 PCI-E (x16) DDR2 ECC/Non-ECC 800MHz, SATA II, SATA RAID, E-ATX
• 8 gig ram
• 2 x Intel Xeon Quad E5420 @ 2.5GHz
• 2 x Zalman CNPS9500A-LED CPU Cooler
• Sapphire ATI Radeon HD 5870 1024MB GDDR5 PCI-Express Graphics Card
• 2 x Samsung SpinPoint F1 750GB SATA-II 32MB Cache
• Sony NEC Optiarc AD-7200S 20x DVD±RW SATA Dual Layer ReWriter
• Lian Li PC-A71B Aluminium Tower Case - Black
• Creative Sound Blaster X-Fi Xtreme Music 7.1 Sound Card
• Microsoft Windows Vista Ultimate SP1 64-Bit
• SST 1200W SST-DA1200 MODULAR PSU

[nimbu]

The green LED only implies that the PSU is outputting that certain voltage on that channel it still could be faulty.

I would try unplugging uneeded equip one by one and trying to power up.

Helps you eliminate things one step at a time.

Nims

[caliston]

The green light is the standby voltage from the PSU... that means it's ready for things like Wake-on-LAN. Very little of the board is actually powered at this point - the light is just to remind you that the board is 'live' and remember to turn off at the Big Real Switch before you plug in things.

ATX uses a soft power switch to tell the PSU to fire up, so check that the switch is connected to the mobo and the mobo to the PSU correctly. If you really want to switch out everything else, you can short the power switch pins on the ATX connector and see if the PSU fan spins up.

[Jay]

I have had a PSU fail but still light the little green light on the montherbord.

[Phage]

Have access to a spare PSU ? It would the easiest way to check before you start any process of elimination.

[TFM]

I am having the same problem after buying a brand new PSU (Corsair vx450w)
MB light on. Fans go round when started.
Do not see MB logo and cannot get into BIOS.
24pin and 4 pin definitely plugged in.
Almost as if 4pin not supplying any power.
Removed battery for a few mins but that made no difference.