9800GX2 will not display. Possibly a problem with the PSU.

trialslife

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Oct 9, 2009
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Hi,

I've just got my hands on a 9800GX2, to replace my 7900gto. I'm running a Jeantech Storm 700W PSU http://www.jeantech.com/storm.htm

The 9800 needs a 6 pin and a 8 pin power supply, the Jeantech unfortuanatly has only two 6 pin terminals to connect to. The two 6 pin terminals, I connected up to a converter, to convert it to 8. For the 6 pin, I converted two 4 pin terminals to 6.

Pressed the power button, the card lit up green. So its definatly getting power, but there is NO DISPLAY.

I've tried both of the monitor outputs, so its not that.

I've also checked, and checked again that the card is in the slot properlly.


Anybody have any ideas on what could be the problem?

Thanks.
 

rambo117

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Jun 25, 2008
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thats pretty screwy indeed...

your PSU uses 4 12V rails, perhaps one of the rails isnt supplying the right amount of amperage...?

most likely its the 9800gx2... may have gotten a bad one out of the batch =[
 

trialslife

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Oct 9, 2009
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Just checked to see if my motherboard has pci-e 2, I think it only has pci-e 1.1 which should be alright I think. Its an Asus PK5.

I have seen posts on another forum, with someone running a Jeantech Storm with a 9800GX2, all working.

Now, before I tried installing the 9800 I did not uninstall/install any new drivers for the card, could this be the problem?

Also, as the card is technically two cards in one, do I need to run something in SLi mode?

Really confused now.
 


There's your problem. I think that if you check the wiring of the adapter, you will find that the adapter is shorting 12 volts to ground. Look at one of the 6 pin PCI-e power connectors. The yellow wires are 12 volt lines, the black wires are grounds. Now, compare it to what the adapter is doing to the 4 pin terminals. If you trace the yellow wires there, I think you will see that the adapter is transposing the yellow wires to ground.

I have been puzzled about the 8 pin PCI-e power thing from the beginning. A 6 pin cable has 3 yellow and 3 black lines and is supposed to provide a maximum of 75 watts. An eight pin cable is supposed to provide a max of 150 watts. OK. More wires, more power. My problem is that the extra two wires are ground wires, so the 8 pin cable still has only three hot wires.

What I would do is remove your adapters and simply plug both PCI-e power connectors from your power supply into the 6 and 8 pin sockets on your video card.

 

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