Power Supply Wont Power up - Gigabyte ga-ma790fx & AMD Phenom 9850

[irishbloke]

Ever since i got this new motherboard and CPU ive been having a bit of a nightmare with it.

Gigabyte ga-ma790fx-ds5 -Latest Bios
AMD Phenom Black Edition 9850,
4 gigs PC 6400 ram (Corsair XMS2 CM2X1024-6400
ATI Radeon 4870

The problem is that the motherboard will NOT power up at all with the 2 of the latest power supplies (600 watt+) i have.

It wont work at all with; (Nothing happens its just dead)
Arctic 600 watt Jeantech PSU (brand new and working)
Corsair 620 watt HX PSU (working)


It only seems to work with my Jeantech 450 Watt PSU and i cant for the life of me figure out why. Ive tried everything to get the board to work with the new PSU's. I had thought that the PSUs i got were dodgy but after testing out one in an older PC it worked fine.

Ive removed all parts and tried powering up and i cant get it to boot up. But the PC seems to work fine with the oldish 450 watt PSU which i find just unbelievable.

Can anyone help with this nightmare? Now on the Gigabyte site the CPU i have isnt listed as supported by this motherboard which is kinda worrying could this be the reason? If so how the old PSU boots up.

I just want to have the fracking thing working with the right PSU.

 

[DaMak420]

if I read the specifications right on your mobo... it implies that it has the 4 pin PCI-e input(power) but it also has the 8pin ATX power conector. (it may be simply removing a cap that is actually right next to the 4 pin connector, thus making it an 8 pin connector (thats how it was on my mobo)

Try using the 8pin power with your new PSU, see if that works.

 

[nickc]

look at this thread, it will explain how to find the problem.

http://www.techsupportforum.com/1010960-post1.html

 

[irishbloke]

if I read the specifications right on your mobo... it implies that it has the 4 pin PCI-e input(power) but it also has the 8pin ATX power conector. (it may be simply removing a cap that is actually right next to the 4 pin connector, thus making it an 8 pin connector (thats how it was on my mobo)

Try using the 8pin power with your new PSU, see if that works.

thanks for the quick replies folks

Ive tried that many times with 2 different Power supplies
Ive tried it with the 4 and then 8 etc over and over and nothing.

I think the only thing i can do now is try my old AMD 6000 CPU in the mobo and rule the mobo out and rule a CPU & MOBO conflict.

This problem is driving me nuts to be honest, paid a lot for this board it was suppose to support AM2+ but it doesnt seem to support the chip i have for it.

There is another thing the PSU i have is well faulty. i.e it powers the motherboard on into a kinda standoff state until i press the power button on the case. So its like just auto powering the board without i guess the usually "checks" a mobo does. Could this be the reason the mobo power ups. And i know this isnt a good situation which i why i need a decent PSU connected.

The official response from Gigabyte wasnt much help;

Thank you for your kindly mail and inquiry. About the issue you mentioned, because the CPU you have is not on the CPU support list, so we can not guarantee the motherboard can work properly with the unsupported CPU.

If possible, please try to test your system with supported CPU and check again, but If the problem still occurs with supported CPU, then a further testing or examination to your system might be required. We suggest you to contact your supplier or nearest distributor and see if they help you to test your system directly. For their contact information, please click HERE.

We are really sorry for the inconvenience you have with our product.

At last, if you still have any further question or suggestion about our products/service, please do not hesitate to contact with us. We will try our best to help you resolve the problem ASAP.

 

[irishbloke]

Just an update;

Tried an old AMd 6000 chip and the motherboard still failed to boot. Tried 3 different power supplies, 4pin and 8pin CPU 12v and still it failed to power up on the 600watt PSU's which are working fine.

so im guessing its a dodgy motherboard. im gonna get it returned and RMA the board.

What do you folks think?

 

[DaMak420]

sounds like a plan!

 

[nickc]

Gigabyte has been bad about that kind of stuff lately, and there support has been lousy.

 

[irishbloke]

Gigabyte has been bad about that kind of stuff lately, and there support has been lousy.

My previous board was an Asus and they seemed not quite good either but the board was reasonably solid except it lacked AM2+ support.

There is another thing the PSU i have is well faulty. i.e it powers the motherboard on into a kinda standoff state until i press the power button on the case. So its like just auto powering the board without i guess the usually "checks" a mobo does. Could this be the reason the mobo power ups. And i know this isnt a good situation which i why i need a decent PSU connected.

I just cant understand why the old PSU works but the new ones dont? any ideas?