Geforce 250GTS on a 570W PSU; why isn't it working?

[kuskus]

Hi everyone, i have a question for you PSU experts..

So i have a computer that i built in early 2006 with the following spec:

- SkyHawk Power ONE 570W power supply

- AMD 3800 X2 processor (OC'd to 2.4 ghz)

- DFI Lanparty NF4 Ultra-D motherboard

- 2gb (2 x 1gb) G.SKILL DDR 500 memory

- Geforce 7800GT video card

- Hard drive i don't quite remember i think its a 250gb Seagate SATA

- Edemax PCI wireless network card


So here is my problem:

I recently bought a Geforce 250 GTS video card to replace the 7800gt, but when i switched them my computer stopped booting up properly and the screen stopped coming on. I also noticed that the system fans aren't quite as vigorous when i turn the computer on.

Now, i know it seems pretty obvious that the problem is the PSU not being powerful enough, but from what i've been reading it seems like 570W should be plenty for this video card.

The Nvidia website says you need a PSU of at least 450W for this card and im well above that.

That's why im comfused.. And i guess im just trying to figure out if maybe i was sent a defective video card before spending more money on a new PSU.

Thanks in advance for any help

 

[yh125d]

Can you be more specific about what happens when you boot? "stopped booting up properly" doesnt tell us much. Is it beeping at all? Do you get a post screen?

 

[kuskus]

Well as i said the screen doesn't even come on anymore, so no POST..

 

[Shmee]

It may be the PSU as I havent heard of the brand b4, not sure of the quality. What are its 12V amp ratings?

It may be a Factual garden variety common sense sucked ass PSU.

LOL ^ inside joke...

 

[Zap]

Three potential problems.

1) Your new graphics card might be dead.

2) Your motherboard might not be compatible with the card (shouldn't happen, but occasionally does).

3) Your power supply is insufficient. SkyHawk PSUs aren't known to always put out what they claim on the label.

 

[Lunyone]

Originally posted by: Zap
Three potential problems.

1) Your new graphics card might be dead.

2) Your motherboard might not be compatible with the card (shouldn't happen, but occasionally does).

3) Your power supply is insufficient. SkyHawk PSUs aren't known to always put out what they claim on the label.

Exactly what I was thinking. You should double check that your GPU has the PCI-e power connections plugged in too (I'm just assuming you haven't checked that since you didn't state it).

 

[v8envy]

Did a quick google on the PSU model and found a few disturbing blurbs. One being "Today?s units at 570 and 470 Watts wouldn't be recommended for a Dual Core processor such as the Intel Pentium-D." on the madshrimps.be review. But that bad boy is rated for 40 amps on the 12v rail, so should be plenty of juice to power up the 8800GTS/9800GTX/GTS250 you're trying to shove in there. Full throttle operation would be a whole different problem address.

More likely problem: does your board support PCIe 2.0? I vaguely recall some people had similar troubles with the 9800GT and friends in some older motherboards which only supported PCIe 1.0. Other than checking to make sure the 6 pin PCIe is connected I'd google for that board and 9800GTX+/8800GTS/250GTS and only then point the accusing finger of shame at the PSU.

 

[Beanie46]

Originally posted by: v8envy
But that bad boy is rated for 40 amps on the 12v rail, so should be plenty of juice to power up the 8800GTS/9800GTX/GTS250 you're trying to shove in there.

What you're missing is while it says the rails can each put out up to 20A, it CANNOT put out a total of 40A combined (you don't simply add rails together to get max output from any rails....+12V or any other); the ACTUAL max. output from the +12V rails is 300W---MAX., NOT the 40A that you get adding the two rails together.

300W = 25A, a far cry from the bogus 40A rail total that's on the power supply.

And I'm betting this is exactly where his problem is located.