My new PC build is dead - help!

zedzed · 24 Feb 2007 at 00:48

Just built a new system from scratch.

C2D 4300
DS3 mobo
2 Gb RAM
2 x HDD
1 x DVD burner
1 x x1950Pro GFX
Antec 6500 case & PSU

Built it all - turned it on - nothing. The PSU doesn't even come on (the fan doesn't spin).

So - what should i do now? This is my first build (although I've replaced a mobo before) - so I'm not a total noob - but still - I'm stuck.

Faulty PSU? Have I maybe not connected something right which would cause the PSU to not even start?

Any help greatly appreciated.

Dez

p.s. I've connected both the 4 pin ATX_v12 connector and the 24 pin one too - not sure if I need both or not. I've also tried just one and not the other - but that didn't work either.

dbmzk1 · 24 Feb 2007 at 01:21

Check the switch on the front of the case is correctly connected to the motherboard. Chances are you either have it in the wrong place, or the wrong way round. Also don't forget PSU's often have a switch on the back. Sounds silly, but I have fallen into its trap many times

zedzed · 24 Feb 2007 at 07:41

The PSU is definitely on at the back. Is the only connection to the motherboard the "Power LED" connection? Or is there another wire?

Dez

Loki · 24 Feb 2007 at 07:47

You should have five connections on your mobo, Power LED, IDE, Reset, Power & Speaker. Form what you have said, the lead from the power button is not connected to the mobo. Without that your system won't fire up

zedzed · 24 Feb 2007 at 07:53

Thanks. Just checked - and I've got 5. I'm assuming "power sw" is the one that I need to check. Does it matter what way round they go onto the pins?

Loki · 24 Feb 2007 at 08:03

It's probably best to check the diagram in the mobo manual. It shouldn't effect it but it's best tjust to check

ca9phoenix · 24 Feb 2007 at 08:24

it's usually the coloured wire to the +ve connector.

hp7909 · 24 Feb 2007 at 08:24

zedzed said:
{snip}I'm assuming "power sw" is the one that I need to check. Does it matter what way round they go onto the pins?

That's it! Wrong way round & it won't power-up. Most mobos, positive side (coloured cable, in this case maybe green) goes in on first pin where its allocated

Trigger · 24 Feb 2007 at 08:47

hp7909 said:
That's it! Wrong way round & it won't power-up. Most mobos, positive side (coloured cable, in this case maybe green) goes in on first pin where its allocated

Case switches are not polarity sensitive- all they do is short two pins. It's only the LEDs that are affected by polarity. Sounds more like he has the power switch in the wrong place completley.

schnipps · 24 Feb 2007 at 08:58

Aye the led's are the only polarity sensitive ones, make sure you get them all in the correct place and refer to the manual as they are fiddly to get in, use tweezers of long nosed pliers if u have problems.

hp7909 · 24 Feb 2007 at 09:00

Trigger said:
Case switches are not polarity sensitive- all they do is short two pins. It's only the LEDs that are affected by polarity. Sounds more like he has the power switch in the wrong place completley.

You sure? Plugged in mine the wrong way a few times & refused to power-up

MeatLoaf · 24 Feb 2007 at 10:52

Do your hard drives spin up? Does the optical drive tray open?

If so you are at least getting power to the board.

The fan dosent spin on the DS3 by default you have to go into the bios and change a setting to get it to spin up straight away.

L_D · 24 Feb 2007 at 11:33

zedzed - If you haven't already it would be worth trying another power cable (unless the one you are using is definately working ok with another system). Similarly - worth trying another power socket if haven't already.

Could also be an issue with the switch on the case - have you got a power on switch on the motherboard itself?

Another thing to check would be that nothing is shorting the underside of the motherboard.

If you haven't already - reseat all components and try again.

Spuderoony · 24 Feb 2007 at 12:46

Check your 20/4 pin connections from the PSU very carefully.

I recently did a build where I'd managed to force the 4 pin connector into the slot the wrong way, so was connecting 12v to ground and vice versa.

And make sure your board isn't touching the case in any place.

Mark228 · 24 Feb 2007 at 13:28

Yep I had something similar with my new build last night. I had all the front case wires plugged in and turned on, got the PSU running but no bootup. Turned out I had the pwrled plugged in wrong (case cable had a three pin and mobo was 2 pin, so I had to snip the middle pin out with scissors). PLugged it in right and it fired up just fine! Amazing what one little wire in the wrong place can do to your new build.