4870 X2 and the 3 red lights!

guessswh0

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Jun 18, 2009
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Hello,

I've searched, read the forums, and still having issues. My card is just giving me three red lights. I have a 730 watt power supply, so I know it's not too little. However, my 8-pin and 6-pin connectors are on the same rail. Would this actually be the cause of it?

My power supply did not come with another 6 or 8 pin connector, only the two on that one rail, and I do not have a molex to 6 or 8 pin connector.

Unless Best buy has it (molex to 6 or 8 pin, which I doubt) I am afraid I would have to rma this card just to make sure it isn't something wrong with the card before my time period runs up. Any suggestions I can try?
 

daedalus685

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Nov 11, 2008
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The 4870x2 consumes about 24A, which is all the power your single rail can provide. Seeing as you have the correct code from the card to indicate a power fault, and that you only have 24A. I am almost certain that you require either A) A new PSU with a larger rail/ better cable setup or B) an adapter that allows you to take power from each rail.

That is a very strange cable setup on that PSU. I thought SLI certification required a dedicated rail for each cable in a setup like that.. but i suppose that just says "SLI/crossfire ready".. tricky...
 

guessswh0

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I agree. Now, I've tried searching... I have a 4+4 pin line coming out of my psu. If I used the 6 pin from the psu (the one that also has the 6+2 pin) and also use the 4+4 pin with some sort of adapter to 8 pin PCIe, would that work to power the card?

And is there any sort of adapter like that? I just tried looking to find it real quick and nothing was really popping up.

I'm trying to hopefully fix this or atleast know if something is wrong before I run out of rma time.

I appreciate your help and responses by the way.
 

guessswh0

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OK, that looks about right. So, I would have to plug my molex connector into the psu, and then plug that adapter into the video card... correct?

And next question, i am guessing that my only other 12v line is my 4+4 pin line from the psu (in addition to the 6 pin and 6+2 pin), so does this adapter still work if it doesn't plug into a 12v line? Or are all lines 12v? I know a good amount about computers, but not as much about how the power supplies work...

thanks
 

guessswh0

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Or one more random question. I don't know if this would fry it or not... but if I were to sand down the square sides of my 4+4 pin, would I be able to plug that into my video card in the 8pin port? Or would that mess up the power situation?
 

daedalus685

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All of the 4 pin Molex, sata, CPU 8pin, and PCIx lines are 12V. You may have to do some checking to see which one is on which rail though, sometimes that info is in the manual, but not always. The only connectors that are not 12V are in the 24pin primary connection (3.3V and 5V are in there).
 

guessswh0

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SO what are your thoughts if i sanded down the 4+4 connector and fit that into the 8 pin connector? Would that cause some power issue that would fry the card?
 

daedalus685

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I can't in good conscience recommend you modify a connector like that. It is a very quick way to get a bricked card, and an expensive one at that. These things are all standard, there is no guarantee that the pin configuration would be the same on a different connector though. I'd have to see it in person to know if it would physically work, though the CPU 4+4 is supposed to be the same +12 opposite the ground though you have to be VERY careful and not mix them up (provided you are going from correct cable to correct cable you could use a paperclip and get it to 'work').

Use good quality adapters for that sort of thing. You should have extra 4*1pin molex for one of the adapters I linked.