Powersupply information on 12v rail & connector for GPU

[watever44]

Hi,

I am looking to add a graphic card to my system, probably a evga GTX 660 from a coworker.
The requirement for the graphic card says 24Amps on 12+V rail.

My powersupply in this system is older but good for my current use and I don't want to replace it, otherwise I might not purchase this video card.

I am wondering if I am reading correctly or not, the information.
+3.3V@36A, +5V@30A, +12V1@18A, +12V2@18A, +12V3@18A, +12V4@18A, -12V@0.5A, +5VSB@3.0A

PCI-Express Connector1 x 6-Pin, 1 x 6+2-Pin

I have 2x3 pin connector making it 6pin. Both are 18amps, so the maximum rating is 36amps ?

Or am I wrong here and my maximum is 18amps, making this psu not good ?

 

[nukemaster]

EDIT. That image did not show when I first viewed this thread. You have 48.3 amps @ 12 volts(580/12) across all rails. A bit of that total will goto the 3.3 and 5 volt rails. this is normal.

My pre edit post.

It would be best to post a model number.

Most multi rail 12 volt power supplies get power from one large 12 volt rail. In some cases it is the same as adding those rails in many more cases it is not the same.

The "rails" are current limiters that had been put in to avoid a user trying to pull the full rated current over a single molex lp4 connector. Since these rails are all connected to one large rail. all of them combined can not pull more than this large rail is rated for. Most of them have a combined rating to tell you how much all these rails can pull combined. Any combination that does not go over what a single rail can handle and all together do not overload the main 12 volt rail works without issue.

Example images.
This power supply has a 16 and 14 amp rail, but can not allow more than 22 combined(that is 264 watts).

Also note the lower rails like 3.3 an 5 volts also come off of this large 12 volt rail so using heavy amounts of those rails will start to cut into the 12 volt rail. This is rarely an issue in most systems however.

 

[nostall]

You should be just fine with that PSU. My EVGA 660's only need one 6 pin power connection each.
Re. amperage: good question.
Newer psu's with multiple "rails" can merge power (for lack of better terms). Keeping that in mind and doing the math it would seem that your total +12V output would be 72 amps: however in reality the total, because of electrical factors, will probably be closer to 60-65 amps combined. EDIT: Nukemaster has the correct figure, ~ 48.3 amps.
I could be wrong, but I believe you will be o.k. with that PSU and that card. Nvidia specifies a minimum 450Watt PSU and that the card maxes out at 140 watts (or 11.6 amps), and even if it hit occasional peaks of 200 watts that would only draw 17amps.

 

[mbarnes86]

Hi

You have 4 x 12V 18 amp rails
Providing the 6pin and 8 pin PCI-e plugs are on different cables they should be ok

What sockets are on the graphics card ?
What is the make & model & power rating of your psu
I guess it must be 900 to 1000 watts if a good quality psu

Googling gtx 660 says 450 or 500 wat psu
140 watts which is 14 amps
Have you got a gtx 660 or a pair of them ?
Or something else

Regards
Mike Barnes

 

[watever44]

My power supply is the one I put the pictures of.

OCZ 600W SXS

It's one video card on an Evga Z97 mini-itx motherboard.

I am not fix on the GTX 660, could be anotherone, R9 270 or something similar. I am looking for a discrete video card not to expensived in the used market. I want to play games like Cities Sky etc... Otherwise the computer is used for streaming Netflix and other video in the living room. (So quiet would be required)

 

[nukemaster]

You are fine with either card.

I think the newegg image was slow to load and that is why so many users did not see it. I did not see it until my post was saved.