Confused: power supply

wittlessgenstein

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Oct 15, 2009
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Hi there,

Have a bit of a scrub question here--am building a new system that includes an ATI hd 4870, which I've recently found out requires 2 PCIe 6pin connectors (I don't have the card yet, but it's in the mail), and my power supply doesn't have a single PCIe 6pin connector, and only 4 4-pin molex connectors. The power supply itself is an 800w thing with 4 12v rails -- at least, they're listed as 12v1 12v2 12v3 and 12v4, each rated for 20amps. I've got a DVD drive and 2 case fans, which leaves me with 1 spare molex. Can I use a y-splitter to power the case fans, and then another y-splitter for the graphics card?

I understand the adapter from molex to PCIe requires 2 molexs, yes? At the moment, I've got what appears to be a single 1-molex to 1 PCIe 6pin, but I don't know where it came from.

Sorry, again, for the scrub question.

witt
 

wittlessgenstein

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Oct 15, 2009
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Not quite -- I lack any 6pin PCIe connectors coming out of the power supply. It only has 4 molex, and then some other cables for the motherboard.

I've seen that the molex-to-PCIe 6pin require 2molex cables to join into 1 6pin. If I have to do that twice that'll consume all my molex connectors and I'll be unable to power my case fans or my dvd drive.

I guess, more generally, I'm wondering what kind of strain I can put on the power supply via molex y-splitters, so that I can power the 2 case fans and the video card.

witt
 

Ron23

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Aug 19, 2009
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i had one of those one molex to pcie addapters when i got my sapphire 4870 they do work but id suggest you get a new power supply if it doesnt have those outputs. You know kind of PSU you have by chance???
 

wittlessgenstein

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Oct 15, 2009
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Hey Ron:

It's a no-name brand, Win Power, and, like I said, it looks like it has 4 12v rails. I didn't pay much for it, and my budget is kind of stretched to its utmost. That said, I'd rather not destroy my video card.

Shadow: I wasn't planning on trusting that 1molex to 1pci-e, because I wasn't 100% certain what it was. I can probably make a go of it with that thing, then.

 

Ron23

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Aug 19, 2009
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Definitely invest in a new psu watts wont matter as far from it being 800 watts .you need the right amount of amps on you 12v rail if all four of you rails dont add up to say 32 or 36 amps it cant be good for your whole system..even a decent 500 watt psu will run it even if you dont have the extra 6 pin connector but this is the kinda PSU i would recommend( i cant stress how important it is to have a good psu it is the most underated part of any system thats why you cant cheap out ...trust me)

http://www.newegg.com/Product/Product.aspx?Item=N82E16817139004