PCI-Express to Molex cable. Why can I not find one?

Status
Not open for further replies.

Jordan Freeman

Solid State Member
Messages
8
Hi there,

I have signed up to this forum in the hopes of finding a solution to my problem. About a month back, I bought a HD6870 for my new PC. This card requires two 6-pin PCI-Express ports from the PSU to run correctly. My PSU has only a single one of these, so I purchased a molex to PCI-E converter from eBay. Looks something like this:

http://www.binbin.net/photos/generic/pci/pci-express-power-converter-lp4to-6pin-pci-exp-.jpg

Upon receiving it, I noticed something odd. There were only 5 pins! I thought this must be common and the sixth pin must be uneeded or something, and so I tried to use it on my GPU anyway and it did indeed work, so I thought nothing else of it. However, after viewing benchmarks of certain games online I have found that my GPU is underperforming significantly in comparison. I thought that the unused pin may be the problem, and that my GPU was not receiving enough power. I looked around and bought another cable, this time from Currys. However, when I received it today I noticed ANOTHER thing odd about it. It's tiny! It's far too small to fit into my GPU, yet it is labelled as a standard PCI-Express cable!

So I came here to ask for help. Am I doing something wrong? Am I looking for the wrong type of cable? This is very frustrating and confusing.

P.S. I'm a UK resident, so no foreign shops! I don't really want to pay loads on postage, unless I really have to.
 
What is the Make and Model of your Power Supply?

When a power supply only has (1) pci-e power connector it usually because it's not capable of supplying enough power for (2) pci-e connectors.

It sounds like your power supply is only capable of supplying the bare minimum to run your card.
 
Here is an image to help better get across my point:

Untitled.png


Notice the top middle pin is missing? All the ones I've seen are like that, for some bizarre reason.
 
what are the rest of the parts in your system?

it might look like your rig is under performing compared with reviews/benchmarks if the rest of your parts are not as good as those used in those benches. many reviewers use OCed i7 systems, or atleast a c2q system, so if you're running on an old stock dual core or something, ofcourse you're not going to be getting the same fps.
 
what are the rest of the parts in your system?

it might look like your rig is under performing compared with reviews/benchmarks if the rest of your parts are not as good as those used in those benches. many reviewers use OCed i7 systems, or atleast a c2q system, so if you're running on an old stock dual core or something, ofcourse you're not going to be getting the same fps.

YouTube - Resident Evil 5 Benchmark on AMD Radeon HD 6870 and Intel Core i5 760 @ 4.0Ghz

That guy has a very similar rig to mine, but he gets roughly twice the FPS. I have an i5 760 with 4GB of RAM.

Okay, odd.. but if i rfemember rightly someone had a galaxy card that had that config. How many wires are on it? 5?

|I found this: OcUK Value PCI Express 6-Pin to 4-Pin Power Adaptor for PCI-E Graphics Cards (RB-527) [RB-527]

But I'd call to confirm its all 6 pins

Thanks, I'll contact them and see what they say.
 
Status
Not open for further replies.
Back
Top Bottom