Is my power supply enough?

[don69]

I just built an i7 Core 920 system with an ASUS P6T SE motherboard, one WD hard drive, one optical drive and two HIS Radeon HD 4650 graphics cards. My case is an Antec Sonata III with the built in 500w power supply. The computer runs great.

Do I have enough power to add a third graphics card? I need two more monitors.

 

[hunter315]

You shouldnt be running two of those on the 450watt, and you most certainly do not have enough power for trifire. You are supposed to have 550Watts for 2 4650's in crossfire, also how many monitors do you really need?

 

[don69]

Hi Hunter, is the same true if I don't plan to run them in crossfire mode? If so, would 650W be sufficient or do I need more?

I use 6 monitors for stock trading, an yes, I need them!

 

[shubham1401]

Ya better upgrade psu......

 

[don69]

I forgot to mention that I don't play games or use any software that use 3D. So I guess the power draw is much less with 2D only?

 

[3Ball]

It would be wise to upgrade the PSU to ensure that the system doesn't go in the future. You are already pushing it with that system, but the real concern is the quality of the PSU that came with the case. Those usually are not to be trusted. As said above, you should probably consider a new PSU.

I recommend the Corsair TX650w PSU: http://www.newegg.com/Product/Product.aspx?Item=N82E16817139005

Best,

3Ball

 

[Onus]

First of all, that's an Antec Earthwatts 500W PSU, a good one.
Second of all, a 4650 uses less power than a 4670, the closest one to it on the GPU power chart I saved from a past THG article, and the closest on the PSU calculator at http://www.extreme.outervision.com/PSUEngine. Checking the latter link, and making a few assumptions about RAM (3x) and drives (2x, in case you add one), Crossfiring a pair of HD4670 needs 327W. It doesn't do three, but you can figure another 60W max (again, for a 4670; a 4650 uses less), for a total of 387W. Your 500W Earthwatts PSU will be just fine; especially since A) those are max numbers, and you said you are doing 2D stuff, not gaming; B) those are for 3xHD4670, not the 3x4650 you are actually using; and C) it is a high quality PSU.

 

[3Ball]

I was unaware it was an Antec Earthwatt. I trust jtt's assessment. I would still watch it closely though.

Best,

3Ball

 

[Onus]

Oh, of course. If it were a 500W Zilchmax, I wouldn't trust it on two cards, let alone three.

 

[don69]

UPDATE:
I have now added a third HIS Radeon HD 4650 graphics card to my system. Everything works fine and the 500W power supply is still cool to the touch. However, I have not tried to run the three GPUs in Crossfire mode or play 3D games. But as a workstation, the new PC works great. Thanks for all your replies.