Please help - new pc not powering up.

[n0s_speed]

hi, i just built a new computer and for some reason it's not powering up. i checked the manual and everything else seemed connected properly.

F_panel = seems like the positive is the colored wire and white is the negative.

system:

AMD FX 8150
Gigabyte 990FXA-UD3
16gb G skill ram
1tb WD caviar HD
1gb pci express 2.1 Radeon HD 6870
750 watts antec power supply


whenever i plug the power cable to the tower and 1st pushed in the start button, i see it light up the LED Fans. then, turn off right away. but doesn't start up everything else....not a single fan. not even the power source built in fan.


any ideas as to why its not powering up? thanks in advance.

[Lisa_maree]

Hi

I always try and test as i go when building a computer. That means installing the CPU and memory in the motherboard and installing that in the case with the power supply. Now connect the power switch to the motherboard. Does the motherboard and power supply start up if so then install the drives. Try the power up again if that all powers up. Install the video card and so on .

So to check that there is no extra stand offs under the motherboard
That there is 2 power leads from the power supply to the motherboard . The 8 pin lead closest to the keyboard socket needs to have the yellow wires to the back of the board.
Using the wrong power supply output is a common cause of computers not starting.

If that isn't the cause there are lots of other suggestions
     

[n0s_speed]

thank you for your reply. yes, i'm using the yellow wires on the 8 pin

[Lisa_maree]

Hi

So on that 8 pin connector the yellow wires are on the side of the connector facing the rear of the board. There is another connector the same on the power supply but it has the black and yellow wires reversed.


Lisa


 

[Computer_Commando]

...So to check that there is no extra stand offs under the motherboard ...     

This is more likely.  It will cause a short circuit on the motherboard & the PSU will automatically shutdown.

[n0s_speed]

i bought the IN WIN BUC Black SECC steel ATX mid tower. It came with only 3 standoffs. I didn't use any of them as I didn't think they were needed. If you look at the pic from newegg below, its a flat surface.

http://www.newegg.com/Product/Product.aspx?Item=N82E16811108395

[Computer_Commando]

i bought the IN WIN BUC Black SECC steel ATX mid tower. It came with only 3 standoffs. I didn't use any of them as I didn't think they were needed. If you look at the pic from newegg below, its a flat surface.

http://www.newegg.com/Product/Product.aspx?Item=N82E16811108395

There are 9 raised standoffs in that picture.  The 3 extras are for those motherboards that need them.  If you're not using all 9 & the motherboard is covering them all, you have a problem.

[n0s_speed]

oh i didn't think those were considered standoffs. anyway, then yes, i've used them all.

I can try to take a pic of the board, if that would help everyone help me figure out the cause? will do when i get home from work.

[Computer_Commando]

>10% failures with this motherboard.
http://www.newegg.com/Product/Product.aspx?Item=13-128-514&SortField=0&SummaryType=0&Pagesize=10&PurchaseMark=&SelectedRating=1&VideoOnlyMark=False&VendorMark=&IsFeedbackTab=true&Keywords=%28keywords%29&Page=1#scrollFullInfo

When I see 8 BIOS versions in 1 year, I would not buy it.
http://www.gigabyte.us/products/product-page.aspx?pid=3996#bios
RMA it today.

Don't know what's happened to Gigabyte in recent years.  I've got one that restarts multiple times before it finally POSTS, very disconcerting.  But it doesn't do it all the time, about 1-3 times out of 7.

[n0s_speed]

you may be right.....i bought the power source tester and the psu is working.....but it still won't power up

just now, i plugged in the old speakers i had LED lights, the lights stays on whenever the power is on from the psu

[n0s_speed]

board was broken. got a replacement and it started working...