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MPG
03-03-2014, 09:36 AM
Hi,

Wanting to install a new graphics card (Asus 7770-DC-1GD5-V2) which I believe draws up to 150W. The power supply I have is a Corsair HX650. Discovered that there wasn't a Molex to 6pin lead supplied with the power supply. Trotted off to my local supplier to see if I could purchase an appropriate lead where I was told that they wouldn't recommend doing what I suggested because there was a risk of fire. In the end they gave me a lead but again stressed I shouldn't use it. I said I wouldn't do so until I had sought more advice.

I was somewhat puzzled about the tech's response which seemed to based on the premise that if Corsair hadn't supplied the appropriate lead then the supply wasn't designed to do what I was proposing. Thinking about that later I concluded the logic was faulty because why on earth would there be Molex plugs on the power supply if I wasn't supposed to use them???? I now wonder whether he was talking about the lead. The one he provided is certainly not a Corsair one. The markings are difficult/impossible to read but the brand is DANYANG. Are there likely to be any problems?

The other specs of the current system are as follows:

Case: Corsair mid tower
Mother board: Gigabyte Z77A-UD5H
CPU: Intel i5-3570
Ram: G Skill Rip Jaws 16 MB
C Drive: Intel SSD 320 120 GB
E Drive: WD Raptor 600 GB
OS: Win 7 Pro

Many thanks in advance for any help/re-assurance.

Michael

pctek
03-03-2014, 10:35 AM
Hi,

Wanting to install a new graphics card (Asus 7770-DC-1GD5-V2) which I believe draws up to 150W. The power supply I have is a Corsair HX650. Discovered that there wasn't a Molex to 6pin lead supplied with the power supply. Trotted off to my local supplier to see if I could purchase an appropriate lead where I was told that they wouldn't recommend doing what I suggested because there was a risk of fire.

Must be an old PSU then, they've had those leads for ages.....

However, no an adapter will not cause a fire.

Worst thing I have seen - where some nong attached an adapter (this on a very old PSU), it wouldn't power the GPU when it went to 3D. That was because the PSU was a lame 250w thing, not because of the adapter.


So long as the PSU has enough power, it will be fine. 650w should be fine.

dugimodo
03-03-2014, 11:03 AM
yeah 650 is plenty for almost any single graphics card, only slight possiblilty of an issue is if it has multiple 12V rails and you put too much load on one of them - unlikely though.
The graphics cards often come supplied with one of those adapters as well, I have a collection of them in my draw.

Agent_24
03-03-2014, 12:52 PM
However, no an adapter will not cause a fire.

It could if the contacts were loose, or the wiring wasn't thick enough for the current being drawn.

MPG
03-03-2014, 01:25 PM
Thanks all for the replies. I don't think the PSU is old. The PC was built late 2012 - maybe that is old these days. I have checked the Corsair manual and it lists the components supplied in the modular cable set. I can identify the spare SATA cables and a peripheral cable and I have a 'spare' not listed in the manual (4 flat plugs, 5 wires/pins with a plug at each end and the other 2 in between). However, I don't have any spare PCI-E cables. Of course they may be installed in the PC. Are these what were described to me as Molex to 6 Pin? Doesn't matter really as I don't have any spares of these.

The only thing that concerns me now is that I see that there are 2 'spare' sockets (Molex? - flat 3 or 4 pin sockets). Are they both +12V or will one of them be -12V? In other words which of the 2 should I plug the power cable in to? I see from the specs that the +12V rail is rated at 52A, 624W.

Thanks for the assistance.
Michael

Agent_24
03-03-2014, 01:54 PM
-12v rail is only used on the motherboard, it's part of the 20\24 pin main connector. Everything else uses +12v

dugimodo
03-03-2014, 02:14 PM
Sounds like you have a single rail so no issues, plug it in wherever and you should be fine.
Molex to 6 pin could well be the ones you want, note though that Molex is a brand not a specific connector type so it really means nothing.
PCI-E are 6 or 8 way plugs, the 8 way often have 2 pins that can be detached to convert to 6 way usage. I'd expect your PSU to have at least two of these and up to 4 maybe spread over two cables.

I have a Seasonic 650W PSU with 4 x 6/8 pin PCI-E plugs running a dual card setup with a 7970 and a 7950 and a FSP Raider 750W PSU running 2 x 280X's so I don't think you have anything to worry about with 1 card on yours.

MPG
03-03-2014, 02:58 PM
Many thanks for the advice. Much appreciated!

I will go ahead and install the graphics card with more confidence.

Michael