PC does not turn on with 9800GT [specifics inside please help!]

[alittlefavour]

just recently purchased a used 9800GT [upgrading from an 8600GT] and it seems i may have an issue with the power or possibly a defective card.

after install my computer does not boot up at all - the first attempt you see the fan spin for a split second and then nothing, the second attempt doesn't do anything not even a noise.


i was under the impression that this card needed a minimum power supply of 400 watts and i [thought?] have a 500 watt supply which has a 6 pin adapter. would i be able to get this card to work with a molex adapter? below is a photo of my actual supply.

 

[DarkSable]

Wait, does the card have a 6- or 8-pin plug?
If so, that needs to be getting power or else the computer won't boot.

Also, it's quite possible that your PSU isn't behaving nicely - cooler master is NOT a reliable brand of power supplies, and if you look, you can see that the maximum power output your 12v rails can provide in total is 360w, and that either single line can only provide 216w maximum. Now factor in the fact that it's not a reliable power supply and shouldn't be trusted to run at its rated power draw, and you could have a problem.

 

[bucknutty]

The 8600 does not require an extra power connecter where the 9800GT does. Make sure you have the 6 pin pci-e power connecter plugged into the card. According to the spec of your PSU it should have 1 connector that you can use for the card.

As far as power goes I don’t think you will have an issue with that PSU. The 9800GT has a max draw of around 110watts. Im guessing your CPU is a Core2duo, those draw around 65wats. If we add in 50watts for board, fans and drives and stuff that puts your total computer draw at around 225-250 watts.

I would check your power cables again, then I would take the card out and reseat it. If that does not work I would try the 8600 again. The 9800gt is used, and it is like 5 years old, there is a chance it is dead.

 

[alittlefavour]

i have a amd athlon 64 CPU... running 4gb ram and two hard drives so i guess that might be an issue... i believe amd uses a bit more power than the intel cpu

i do have a 6 pin pci-e power connector that comes from the suppy that i did plug into the card but still no luck.

if the card was defective wouldn't the computer still turn on but nothing would display?

does a molex adapter help at all or thats strictly for a power supply that doesn't have a 6pin?

taking a guess here because i don't know too much about power supplies and i'm not able to make out exactly what that grid means but do the bigger connectors supply more power thus making the molex adapter a possibility for the card to work instead of using the 6pin cable?

 

[bucknutty]

A bad card can do lots of things. It might prevent the computer from booting, it might cause blue screens, or it might just not show video.

In this case the computer works fine with the 8600, but when you plug in the 9800 it wont even post. That suggests to me the card is broken, not seated correctly, or there is some type of compatibility issue with the board.

I dont think the issue is the PSU. You can try the molex adapter, heck it can't hurt.

The power numbers I estimated above are at max draw(when the computer is working very hard). Just to power up and sit at the desktop at an idle the computer would only need like 100 watts. If the computer was shutting down randomly or when a game was started then i would guess a bad PSU.

 

[Onus]

If I'm not mistaken, the card will [try to] draw full power until the drivers load, at which point it settles down. It could still be the CM PSU, which is near-junk, although according to http://www.hardwaresecrets.com/article/Cooler-Master-eXtreme-Power-Plus-500-W-Power-Supply-Review/728/10 it actually is capable of 500W (it sucks for other reasons). Does this card work in another PC?

 

[alittlefavour]

If I'm not mistaken, the card will [try to] draw full power until the drivers load, at which point it settles down. It could still be the CM PSU, which is near-junk, although according to http://www.hardwaresecrets.com/article/Cooler-Master-eXtreme-Power-Plus-500-W-Power-Supply-Review/728/10 it actually is capable of 500W (it sucks for other reasons). Does this card work in another PC?

that's my next step -- finding a computer with a supply well over 500 watts that i can try testing on. i may or may not be able to do this though...

 

[bucknutty]

About the label on the PSU. Some PSUs are labeled in a more "fair or honest" way than others.

Cooler master has a reputation for bad labeling, that is why many people will say they are low quality.
For example your label states. The 3.3volt rail is good for 22amps. 3.3volt x 22amps = 73 watts
The 5 volt rail is good for 25 amps. 5x25= 125watts.
Then it states the combined load on both the 3.3 and 5 is only 165 watts? According to our math it should be closer to 200. That is sort of irrelevant any way because the 3.3 and 5.5 are only used for fans, usb, and hdds. 165 watts is a lot of power for hdds. Do they think your going to run 15-20hdds?

The 12volt rail is really where all the work is done. The CPU, mother board, and GPU are almost 100% 12volt.
So in this case we got rail1 good for 12volts x 18amps = 216 watts.
We also have rail 2 good for 12volt x 18amps = 216 watts. So one might expect the PSU to be good for 432 watts of power on the 12 volt. But wait they then list a combined 12 volt draw of only 360? Why is that? Because they are using cheap parts and over inflating the PSUs capability.

So in this example we have PSU advertised at 500 that can only give us 360watts of usable 12 volt power.
If you were to compare this label to a more expensive brand PSU like a Seasonic or an Antec the usable 12 volt rails would be almost exactly 500. This labeling game is the cause for many people to perceive the PSU as being low quality.

All that said we have 360 watts to work with. We know the 9800gt only needs 110. Athlon 64s draw around 90 watts. Again 50 for all the other stuff puts the full draw of the computer at 250-300. That should be a good 50-100 under the stated capacity of the PSU.

Normally the 6pin PCI-e connector is wired to draw equally from both rails, so it is the ideal connector for the video card. But in reality we have no idea how the PSU is wired.

 

[bucknutty]

Thats alot of text sorry if i got carried away. Testing the video card in another computer is a good idea.

 

[alittlefavour]

no that's fine i appreciate all the quick and sometimes in depth responses that's more than i could of asked for

thanks.. and ill see what happens with this card.. i really wanted to get it to work before i got sim city (the new one)

 

[haider95]

doesn't look like a PSU problem to me dude, I managed to run a 9600GSO With 8800gts bios on a 250w psu. Its definitely not your PSU. Try the card on another system just so u can rule out the power supply

 

[sam1911]

9800GT aint a good card nowadays ,It cant play modern games BTW the card maybe defective so if possible return it and buy a new DX 11 card .Also i have seen many other having problems with that PSU but I have a CM 600 and works nice with my GTX.