CF HD 6950 vs SLI GTX 560

[kennyj313]

Hey guys, I'm in the process of selecting parts for a new system I'm planning to build as soon as the LGA1155 motherboards come back in stock. I have all of my other parts selected, but I've run into a problem in the GPU department. I'm debating between CF 6950's and SLI 560's. Right now I'm planning on getting a 750W PSU and I'd like to stay as close to $500 as I can for the GPU(s).

The main problem I'm having is with Eyefinity/ Surround. I currently use an HD 5770 hooked up to 3 19" 1280x1024 LCDs (2x DVI 1x mini DP w/ active DVI adapter) and a 24" 1920x1080 LCD (HDMI). I mostly use the 3 smaller monitors for general multitasking and only occasionally switch over to a spanned setup for gaming, while I normally switch over to the 24" for gaming. I feel like the reason I don't use the spanned setup more is because I only have the horsepower to drive older games with it.

I was mainly leaning towards the 560's, but I have read that they tend to run into a major vRAM bottleneck once you start to hit ultra high resolutions, making the 2GB 6950 seem like a better choice. HOWEVER, I have also heard that using mixed connections on CF cards results in tearing with v-sync enabled. I also know that Palit does make a 2GB 560, and it's about the same price as the 2GB 6950's.

So it comes down to 2 questions:
1. Are the screen tearing issues/ vRAM bottlenecks really significant issues, and if so:
2. Which solution is the better choice?

I'm also not locked in to these solutions, so alternatives are also fine!

 

[kennyj313]

Any input would be greatly appreciated! Also, I plan on getting a Cooler Master Storm Scout case, does anyone have any idea whether there will be any issues with space with either of the two potential setups?

 

[stingstang]

As far as I've read in to tearing and V-sync, tearing is due to excessive framerates with dual-graphics configurations, and v-sync limits framerates to eliminate that. According to other posts I've read on this site, the 1gb limit on last-gen graphics cards is beginning to get used up in modern games, so I would suggest something more than that. The 6950s are overall better cards than the 560s, and natively have 2 gb of VRAM integrated, so there's no chance that it's a marketing gimmick, buying a card with more than normal VRAM, which sometimes happens.

 

[kennyj313]

I know that's exactly what V-sync usually fixes, but from what I've seen, there are issues with using it in CF/ Eyefinity setups. I'm not making my choice based on what people say on the strict 1v1 performance of the cards because I've seen completely conflicting information over and over, and it's close enough that it doesn't really matter to me. What matters to me is the specific problems that might come up with my setup.

 

[17seconds]

One consideration is: how much heat and noise is added with the addition of a second card? The GTX 560's will be much better in that respect. In fact, in these reviews, the 6950's idle noise is louder than the GTX 560's at load. Similarly, the 6950's idle temperature is 3c higher than the GTX 560's at load.

Noise: single card/dual card (difference)
560: 37/40 Dba (+3 Dba)
6950: 41/49 Dba (+8 Dba)

Temp: single card/dual card (difference)
560: 68c/74c (+6c)
6950: 77c/89c (+12c)

http://www.guru3d.com/article/geforce-gtx-560-ti-sli-review/1
http://www.guru3d.com/article/radeon-hd-6950-crossfirex-review/1

 

[kennyj313]

One consideration is: how much heat and noise is added with the addition of a second card? The GTX 560's will be much better in that respect. In fact, in these reviews, the 6950's idle noise is louder than the GTX 560's at load. Similarly, the 6950's idle temperature is 3c higher than the GTX 560's at load.

Noise: single card/dual card (difference)
560: 37/40 Dba (+3 Dba)
6950: 41/49 Dba (+8 Dba)

Temp: single card/dual card (difference)
560: 68c/74c (+6c)
6950: 77c/89c (+12c)

http://www.guru3d.com/article/geforce-gtx-560-ti-sli-review/1
http://www.guru3d.com/article/radeon-hd-6950-crossfirex-review/1

That's definitely something I hadn't considered. 74c vs 89c is a pretty big difference, especially with regards to overclocking potential. I'm pretty much settled on the 560 now, but I'm still a little worried about the vRAM bottleneck. Is it worth the extra $60 to go with two of the 2 GB Palit versions over the Gigabyte (that's what I'm planning on getting) version?

 

[HostileDonut]

I would get the the two hd6950s and unlock and OC them. BTW, what PSU is that???

 

[kennyj313]

I would get the the two hd6950s and unlock and OC them. BTW, what PSU is that???

I was originally going to go with a Corsair 850W, but someone suggested THIS on the basis that you don't need 850W for SLI 560's or CF 6950's

 

[JackNaylorPE]

The Antec TP series is a great PSU ... you can see its little brother get a 9.5 performance rating here:

http://www.jonnyguru.com/modules.php?name=NDReviews&op=Story4&reid=140

But for the same $100, you can get the 10.0 performance rated XFX Black Edition

http://www.newegg.com/Product/Product.aspx?Item=N82E16817207003

http://www.jonnyguru.com/modules.php?name=NDReviews&op=Story5&reid=184

And, I'd go with the twin 560 Ti's

 

[HostileDonut]

I have heard that the NEW antec 750 can supply 900w. Get the hd6950s and unlock and OC. It will blow two GTX560 Ti's out of the water!

 

[HostileDonut]

Btw, you have the NEW antec 750w then, not the old.

 

[kennyj313]

The big question still hasn't been answered - is the vRAM bottleneck I mentioned really significant? Most of the charts I've been looking at have the 560's performance falling off pretty heavily at high resolution supposedly of the 1 GB of vRAM. If it is, I'll probably go with the 6950 since I plan on using ultra high resolutions with Eyefinity/ Surround.

 

[HostileDonut]

The big question still hasn't been answered - is the vRAM bottleneck I mentioned really significant? Most of the charts I've been looking at have the 560's performance falling off pretty heavily at high resolution supposedly of the 1 GB of vRAM. If it is, I'll probably go with the 6950 since I plan on using ultra high resolutions with Eyefinity/ Surround.

Yes, the hd6950 would be the better choice for VRAM, and overall performance considering that you can unlock it to a hd6970 and then OC from there.

If I were in your shoes, I would go for the hd6950 in a heart-beat. Does that answer your question?

 

[kennyj313]

I've done a little more research on my own and it seems like it is a pretty big deal at high resolutions. I've also found very little about the screen tearing issues, and it seems to be a pretty uncommon thing. So, I'll probably be going with the 6950's after all. Thanks for all of the help!

 

[kennyj313]

Best answer selected by kennyj313.

 

[HostileDonut]

Anytime.

 

[17seconds]

Be sure to scout out the ones with the quietest/coolest heatsinks.

 

[kennyj313]

Be sure to scout out the ones with the quietest/coolest heatsinks.

I plan on it, I'm already looking!

 

[Mousemonkey]

This topic has been closed by Mousemonkey