6PIN TO 8PIN safe to use?

wizball

wizball

wizball

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I'd like to buy -


YOUR BASKET
1 x "Quasar 210i" Intel Core i5 4670K @ 4.2GHz Overclocked Haswell Gaming PC Bundle £371.99
- 1 x No Memory Upgrade £0.00
- 1 x Standard Build Systems - Approximately 5-7 working days £0.00
1 x Gigabyte GeForce GTX 760 WindForce 3x OC Rev2 2048MB GDDR5 PCI-Express Graphics Card **Black PCB** £199.99
1 x Microsoft Windows 8.1 64-Bit DVD - OEM (WN7-00614) £71.99
1 x Akasa PCI-E to PCI-E 2.0 Adapter (AK-CB052) £2.89
Total : £658.86 (includes shipping : £10.00).



but I read somewhere that you should avoid using psu lead adapters?
this is my old psu which has 2x6pin pci conectors.
28548---OCZ-OCZGXS600-600-Watt.JPG


will it get enough power to the gcard using the adapter?? thx in advance
 
You should be fine using that cable, ones which I don't like using is Molex to PCI-E adapters.
 
Hmmm, may not be a wise choice; 6 pin pci-e rated at up to 75watts and an 8 pin is up to 150 watts

adapters for 2x 6pin to 1x 8pin would be fine. otherwise it could cause problems in my opinion
 
flying grouse said:
Hmmm, may not be a wise choice; 6 pin pci-e rated at up to 75watts and an 8 pin is up to 150 watts

adapters for 2x 6pin to 1x 8pin would be fine. otherwise it could cause problems in my opinion
Click to expand...

I'm wondering this too. What doesn't make sense is the sticker on the PSU says 4x 12 V rails each at 18 A, suggesting each rail can deliver 216 W. If it comes with 2x 6 pin connectors though one assumes they connect to rails 2 and 4, but as you say they'd be way over spec?

Perhaps he should use rail 1 for CPU, rail 3 for mobo, and combine rails 2 and 4 into a single 8 pin connector for the GPU? :confused:

Modern single rail supplies are so much easier! :p
 
joeyjojo said:
I'm wondering this too. What doesn't make sense is the sticker on the PSU says 4x 12 V rails each at 18 A, suggesting each rail can deliver 216 W. If it comes with 2x 6 pin connectors though one assumes they connect to rails 2 and 4, but as you say they'd be way over spec?

Perhaps he should use rail 1 for CPU, rail 3 for mobo, and combine rails 2 and 4 into a single 8 pin connector for the GPU? :confused:

Modern single rail supplies are so much easier! :p
Click to expand...

How the PSU supplies the power is completely and utterly irrelevant.

The bottom line is the 6 pin connectors as per the PCI-E spec are rated for 75W.

Over three +12V wires means 25W each of give or take 2A.

Depending on the gauge, they might be able to supply 4A necessary for 150W operation or they might not.

However, generally I suspect they are from reputable manufacturers.
 
If the wires can take the ampage and the rail can supply it then no issue, each PCI-E 12v connector has 18A according to the side of the PSU (or is that combined?) so it can deliver the power and you would expect if it can deliver the power it's wires will be able to take it, and the 6-8 pin adapter is obviously designed to take it as that's its job, so all good :)

I was quite surprised when I got my new PSU that the PCI-E plugs were doubled up on each modular GPU cable, they have a 6+2pin that then daisy chains off another 6+2pin.
 
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I use two of those adapters, one for each of my 7970s, as my PSU has 2x8-pin and 2x6-pin cables (I need 4x8-pin). Smooth sailing so far :)
 
The 6 pin and 8 pin connection system is over engineered to reduce the amount of current running through the connector and reduce the amount of heat generated in the wires and connectors.

Molex specify that that connector system in use is good for 9A per circuit on 6 and 8 way connectors. The maximum a card is supposed to draw is 12.5 from any socket so there's still plenty of headroom.

The cables can carry 10A each at least.

Individual terminals are good for 13A.
 
A 6 pin adapter can provide less power than an 8 pin adapter can't it? Or at least that's how it used to be? I assume it still is otherwise having the two different connectors seems pointless. Unless it just affects how the power is distributed?

So using a dual 6 pin to 8 pin adapter would be fine, but I wouldnt use a single 6 pin to 8 pin adapter even if it is included.

My GPU (GTX670 TOP) came with a dual molex to 6 pin adapter, and i'm not going to use that in a hurry. :p

If someone wants to prove me wrong (with conclusive evidence) then i'd be happy too because I could use a 6 pin to 8 pin adapter in my Dell. (I know, dirty word.)
 
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joeyjojo said:
I'm wondering this too. What doesn't make sense is the sticker on the PSU says 4x 12 V rails each at 18 A, suggesting each rail can deliver 216 W. If it comes with 2x 6 pin connectors though one assumes they connect to rails 2 and 4, but as you say they'd be way over spec?

Perhaps he should use rail 1 for CPU, rail 3 for mobo, and combine rails 2 and 4 into a single 8 pin connector for the GPU? :confused:

Modern single rail supplies are so much easier! :p
Click to expand...

If you look at the Label it quotes 580W "combined power" for the 4x 12v rails, so each rail cannot provide 216W
 
Shh :D

What I meant was is it safe though? :( Not all PSU's are built to the same standard. I have no idea if the 6 pin plugs on my 6 year old 875W Dell workstation PSU will be cool with it :p
 
Concorde Rules said:
How the PSU supplies the power is completely and utterly irrelevant.

The bottom line is the 6 pin connectors as per the PCI-E spec are rated for 75W.
Click to expand...

It is relevant though, if the OP starts using the same connectors for everything.
The +12V power rail is "virtually" divided into 18A pieces just as the standard demands. It’s good that the label tells clearly which connector is powered by which line. The wires of the different lines are color-coded in the connectors: yellow for the 12V1 and a combination of yellow with black, blue and green for the other three lines.
Click to expand...
http://www.xbitlabs.com/articles/cases/display/atx-psu6_5.html

So as I said, if he wants to stick to the standards (75W through a 6 pin connector as you point out) he needs the two 6 pin connectors he's got (rails 2 and 4 presumably) into a 2x 6 pin -> 8 pin adapter -> graphics card.

Good explanation here: http://forums.pcper.com/showthread.php?433449-4-pin-to-6-pin-pci-e-adapter&p=3977981#post3977981

However, OP could still easily get away with one 6 pin to 8 pin adaptor, because in a 8 pin connector there are still just 3 circuits (source) so as Tealc says the max you'll get through each would be a bit over 4 A if they pulled the full 150 W, which is below the rating of the wire and connectors.
 
joeyjojo said:
So as I said, if he wants to stick to the standards (75W through a 6 pin connector as you point out) he needs the two 6 pin connectors he's got (rails 2 and 4 presumably) into a 2x 6 pin -> 8 pin adapter -> graphics card.
Click to expand...

Problem with that is his card needs a 6pin and an 8pin connecting (well, it doesn't need it but those are the sockets it has).
 
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