Power Supply Problem?

[HazChem]

My system currently has a 420-Watt power supply and it is powering a Pentium 550, Intel 925x mobo, x850xt video card, a sound card, 3 hard drives, dvd drive, dvd writer drive, 2 120mm fans, 2 80mm fans, a swiftech pump, and some lights.

I just recently upgraded my 19" LCD to a 23" LCD and it was working fine for a day and now it won't start up. I don't even get a POST. When I connect it back to the 19" LCD, it works fine. I tested the 23" with another computer and the screen is fine.

Is it because the power supply doesn't have enough juice to run my accessories? Or could the video card be the problem?

Some additional info: When using 19" screen, I am not able to run 3DMark05 since the videocard shuts down 30 seconds into the test. I figured this was because it was drawing too much juice.

Any help would be great.

Thanks!

 

[Conky]

What brand of P/S are you using?

My guess would be that it is a power issue. You might try disconnecting some components and seeing if the problem goes away to confirm this.

 

[pcgeek11]

Is it not cranking out enough power for my ...

It looks like you got a big load and need a power supply with a bigger crank!

I couldn't help myself...

pcgeek11

 

[HazChem]

Update: I changed out the video card and now it works. I removed a year-old HIS 850xt video card for a cheapie stock x600 card that originally came with the desktop (good thing I saved it...).

I'll check on the P/S brand when I get home.

Later this week I'll check to see if it is the P/S or the video card.

Thanks for your help guys.