Is this PSU crossfire compatible?

[skyywalkr]

Can I crossfire two decent cards (R9 200 series) with this PSU?

I'm not entirely sure.

http://www.newegg.com/Product/Product.aspx?Item=N82E16817151132

 

[i7Baby]

Yep - up to 2 x 270x's

 

[4745454b]

He can go higher then that. 280x's on that should be alright. Wouldn't OC anything in that case but that PSU can do it.

 

[i7Baby]

2 x 280's should have a good 800W psu - a bit over what he's got.

 

[skyywalkr]

Thanks for the input, I've got a R9 280. Was looking to maybe crossfire two someday.

 

[4745454b]

Why would he need an 800W? A gold 750 has more available power then a bronze 800, probably even a bronze 850.

280X is a 250W part. Two of them is only 500W. Even if he had an FX CPU that used 125W, the rest of the system is less then 200W. 500W + <200W = <700W, which a Seasonic Gold rated 750W unit should have no problems with. I wouldn't power two 290s on it, but up to 280/280x should be fine. (And as I said you don't OC anything.)

 

[i7Baby]

Its what RealHardTech recommend.

2 x 280's need 800W (per RHT again).

Usually about 300W is allowed for the rest of the system. You can also check eg http://extreme.outervision.com/psucalculatorlite.jsp - capacitor aging, cpu overclocking, fans, usb devices, etc etc etc

 

[i7Baby]

Link to what?

 

[4745454b]

Can you link? I'm at work on my phone, search isn't fun. I didn't easily see a cf review of the 280x, but look at this.

http://www.guru3d.com/articles_pages/radeon_r7_260x_r9_270x_280x_review_benchmarks,10.html

Here is an overclocked six core i7 with the 280x using 350W. Another 280x they say is another 241W, for a total of ~600W. I showed the math earlier, a good 750W will have no problems.

 

[4745454b]

A link to the realhardtech article. Perhaps if I saw how they tested I can figure out how they can be so off. The 280x is the 7970GHz. I've never seen a CF setup for either card that crosses 700W. The one I linked says ~600W. Here are some more.

http://www.techpowerup.com/reviews/ASUS/HD_7970_CrossFire/22.html (note that this is the original 7970, for the GHz edition feel free to bump the power consumption up to perhaps 600W?)

http://www.techspot.com/review/546-amd-radeon-hd-7970-ghz-edition/page11.html Single 7970GHz at 354W. Add another 250W card and you get ~600W.

http://www.legitreviews.com/asus-radeon-hd-7970-3gb-crossfire-review_1834/11 7970 in CF, Probably 700W for the GHz/280x.

http://www.tomshardware.com/reviews/radeon-r9-280x-r9-270x-r7-260x,3635-18.html System with single 280X is 257W, add in another 250W card and you are ~500W. (This is oddly low.)

http://www.anandtech.com/show/7400/the-radeon-r9-280x-review-feat-asus-xfx/20 I did say no OCing, so lets stick with the 280X DD. Using the even higher Furmark numbers that's 360W + 250W = 610W.

Do I need to continue? Using stock 280X cards in real world gaming cases you are pulling 600W. Maybe less. IDK why that one site said 800W. A Seasonic built 750W gold rated unit will have no problem supplying 600W+. Again, it won't be a problem.