PCI-E 6+2 question

QueBert

Lifer
Jan 6, 2002
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My PSU has 1 6+2 connector, my new video card has an 8 pin and a 6 pin. Googling I read conflicting things about how to handle this. A few people recommended getting a 6+2 y adapter. A few others said no no no and to get a new PSU. My PSU's plenty powerful enough, Corsair 520 watt (i5, 7950) I can some what see the no people's stance. But I'm not too sure that using a splitter will put un-needed stress on the rail.

My question is, is there any reason I should go with a PSU that 2 6+2 connectors out of the box over using a splitter?
 

lehtv

Elite Member
Dec 8, 2010
11,897
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What exactly is your power supply? If it's the Corsair HX520, it should have two PCIe connectors. I don't know of any other 520W Corsair units.
 

QueBert

Lifer
Jan 6, 2002
22,979
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No reason to get a new psu. Just get a LP4 to 8 Pin PCI Express Video Card Power Cable Adapter
and you are set.

Video card came with that, I only have 1 molex connector and I'm not sure if it even works. I have no stuff with molex to hook it up and test it out. I believe that connector is bad. Just a hunch, but the video card that's not working is brand new. Could be DOA I dunno. I ended up ordering a EVGA Hadron case today. If it doesn't work in that I know it's the card.

Or I guess it could be the Motherboard, DOH lol.
 
Nov 26, 2005
15,194
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Didn't the GPU supply the connectors? Every graphics card I buy offers cables for the necessary connections, :hmm:
 

aigomorla

CPU, Cases&Cooling Mod PC Gaming Mod Elite Member
Super Moderator
Sep 28, 2005
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never split a PCI-E rail.

Those were meant to handle a certain type of current... the reason why a video card can take 2, is because it requires more current then 1 can handle.

The reason why some cards require a 6 vs 8 is again.. current... those 2 extra wires allows more current.

If you split the rail, you will effectively double the current which those wires can handle which can lead the wire to overheating, and then a fire hazard.

This was quite normal on guys who did TEC setups POORLY, pulling too much current from a single Molex wire.

Your best off getting the second PCI-E rail off a Molex and then using an adapter...


Here an exaggerated example of a wire under too much current:
http://www.youtube.com/watch?v=o_bIa_uau0c

Dont use the same PCI-E wire to split 2 PCI-E connectors... your asking for danger.
 
Last edited:

fx_rage

Senior member
Mar 21, 2011
331
0
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I'm currently sleeving my own set of PSU cables (for the x650) and they have a set of 6+2 which connects to the PSU via an 8 pin, and then splits to provide 2 6+2 connectors.

I assume this is fine and if so, is it ok because it's attached to an 8 pin to the PSU?

never split a PCI-E rail.

Dont use the same PCI-E wire to split 2 PCI-E connectors... your asking for danger.
 

Meghan54

Lifer
Oct 18, 2009
11,684
5,228
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The reason why some cards require a 6 vs 8 is again.. current... those 2 extra wires allows more current.


Aigo, I think you'll find that the two wires on a 6+2 PCI-e connector that make it an 8-pin connector are nothing more than two sense/ground wires and don't actually carry current. But you are correct in that when the two ground/sense wires are inserted into the 8-pin connector on a gpu, that allows extra current to pass across the three + wires on the 6-wire side of the 6+2 PCI-e connector.
 

Golgatha

Lifer
Jul 18, 2003
12,400
1,076
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If that's the one, he's got 2x6pin PCIe cables. OP, you just need a 6pin to 8pin PCIe adapter.

Something like this:

http://www.amazon.com/StarTech-Expre.../dp/B001TK3TJY

It never ceases to amaze me that a problem with an absolutely direct solution to the problem can generate so many opinions about the problem when the problem is easily and directly solvable. OP, buy the adapter I linked, install it, and go about your day. There is no worry of overvoltage, frying wires, overloading rails, etc.
 

aigomorla

CPU, Cases&Cooling Mod PC Gaming Mod Elite Member
Super Moderator
Sep 28, 2005
21,073
3,576
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It never ceases to amaze me that a problem with an absolutely direct solution to the problem can generate so many opinions about the problem when the problem is easily and directly solvable. OP, buy the adapter I linked, install it, and go about your day. There is no worry of overvoltage, frying wires, overloading rails, etc.

im confused...

his problem is he is lacking a extra pci-e rail? or he is lacking a 8 pin...

if he needs another pci-e rail, he would need to pull it off the molex like this:

cputopiaonline_2270_12496967


if he is missing 2 pins... then yes ur adapter will work.


However he mentioned a Y splitter... which lead me to think he is missing an entire PCI-E rail.