6770 crossfire or 6950

[Soup]

Hello,
Been lurkin TPU for a long while now but this is first post.

I am building a secondary machine and would like some opinions on the GPU setup.

On your marks

Should I do two HD 6770's in crossfire? Or one HD 6950?

Get set

Both choices run at just about the same price.

GO!

 

[Damn_Smooth]

6950 has a better upgrade path and I'm not sure that 2 6770's equals one 6950, so I would go with that.

 

[Jetster]

^ Agreed

 

[BrooksyX]

I would get a 6950. Less hassle

wish I had a 6950/6970 over my 6870. oh well its still a pretty good card

 

[DrunkenMafia]

6770's are pretty crap mate. 6950 is a much better option.

100% 6950. Even it it was $100 more.

 

[Fourstaff]

Compromise with 6870 then CF down the line, or 6950. 6770 is useless in the event CF doesnt like you (small but distinct possibility)

 

[John Doe]

Unless you can find reference (which all unlock and have the best PCB with Volterra Digital PWM), this one should be your best bet I think

MSI R6950 Twin Frozr II OC Radeon HD 6950 2GB 256-...

 

[Anusha]

6770 = 5770 = 1/2 of 5870 -> CF5770 will match a HD5870 at 100% scaling, which doesn't happen more often than it does.

HD5870 ~ HD6950 so basically you are getting performance of HD6950 only at best case of HD6770. i'm sure CFX6770 uses more power, uses up two slots, runs hotter (at least one card might), and might give driver problems. and if you buy the 2GB model, you get 2GB! (did you expect something else? )

HD6950 HANDS DOWN WINNER!!!

but i would recommend that you get something with a better cooler than the reference crap. even if you have to give up unlockability, unlocking gives only 1-2% boost. overclocking gives much bigger boost. so get something with an awesome cooler and that can tune voltage.
if you want something that doesn't

 

[John Doe]

The only problem with reference is stock cooler. You get further than %1-2 more performance from 6950 to 6970, and reference has dual-BIOS along with Volterra Digital PWM. Reference "is" the best 6970. It has the highest quality PCB. All it needs is a custom cooler on top of it.

VisionTek 900352 Radeon HD 6950 2GB 256-bit GDDR5 ...

 

[wolf]

6950 2gb no question at all, unless you wanted to pick another card around this cards power like a GTX570 I guess. In any case avoid deliberately buying two lesser cards from the get-go.

 

[Volkszorn88]

The 6950 mate, you'll thank your self down the road. Especially if you want to add another card down the line, you definitely won't be dissapointed.

1x 6950 for now
2x 6950 for later

 

[Anusha]

The only problem with reference is stock cooler. You get further than %1-2 more performance from 6950 to 6970, and reference has dual-BIOS along with Volterra Digital PWM. Reference "is" the best 6970. It has the highest quality PCB. All it needs is a custom cooler on top of it.

VisionTek 900352 Radeon HD 6950 2GB 256-bit GDDR5 ...

I said 6950 unlocked vs stock 6950. Not 6970 vs 6950.

6950 @ 6970 clocks but locked is only 1-2% slower than 6970. Clocks matter more than shaders.

 

[John Doe]

No, they don't. 800 Mhz of 6950 against 880 of 6970. Look at the difference.

http://www.anandtech.com/bench/Product/331?vs=292

It's the shaders that make it up. It's not %1-2 more. Not even close. Or let's compare a stock 470 to a 480. 600 to 700 Mhz difference, but 448 to 480 shaders.

http://www.anandtech.com/bench/Product/311?vs=309

 

[LDNL]

6950(70), the 6770 is just a rebranded/named 5770

 

[Anusha]

No, they don't. 800 Mhz of 6950 against 880 of 6970. Look at the difference.

http://www.anandtech.com/bench/Product/331?vs=292

It's the shaders that make it up. It's not %1-2 more. Not even close. Or let's compare a stock 470 to a 480. 600 to 700 Mhz difference, but 448 to 480 shaders.

http://www.anandtech.com/bench/Product/311?vs=309

It's not. It's the clock speed at least with 69xx. Check with people who have unlocked. They are only saying it only gave them a 1-2% boost.

And this review shows it. (at the end)
http://www.techpowerup.com/articles/overclocking/vidcard/159

See 1408->1536 is 9% boost and 800MHz to 880MHz is 10%. Should be comparable. But it's 3.7fps vs 8.9fps. More than double.

 

[TC-man]

Hi,

I also can recommend you to buy the HD6950, since I don't think you will like the micro-stuttering in games that's caused by the 2x HD6770 in Crossfire setup. You can reduce the micro-stuttering by adding another one HD6770 (that would be 3 videocards in your PC; more info here). And not all games work great with Crossfire, some don't even work correctly and you will have to disable one gpu.

 

[Xaser04]

The only problem with reference is stock cooler. You get further than %1-2 more performance from 6950 to 6970, and reference has dual-BIOS along with Volterra Digital PWM. Reference "is" the best 6970. It has the highest quality PCB. All it needs is a custom cooler on top of it.

VisionTek 900352 Radeon HD 6950 2GB 256-bit GDDR5 ...

As long as you run an aggressive fan profile (read: control it using MSI afterburner) the reference cooler is excellent.

Mine, despite running three screens (thus higher clocks) is basically silent for normal use and only ramps up to noticable levels after a lengthy gaming session.

As standard the CCC ramps up the fan far too quickly for my liking thus giving the impression of a louder cooler.

As for the performance difference with the unlocked shaders; my advice is simply clock the HD6950 instead. Mine unlocked which is great (Asus reference card) but the biggest performance boost comes from upping the card to HD6970 clocks and NOT from the extra shaders.

 

[de.das.dude]

6950. you can crossfire a 6950 in the future. plus i think they will consume less power than the cfx

 

[LordJummy]

No, they don't. 800 Mhz of 6950 against 880 of 6970. Look at the difference.

http://www.anandtech.com/bench/Product/331?vs=292

It's the shaders that make it up. It's not %1-2 more. Not even close. Or let's compare a stock 470 to a 480. 600 to 700 Mhz difference, but 448 to 480 shaders.

http://www.anandtech.com/bench/Product/311?vs=309

You are incorrect.

The clocks are significantly more important, as the additional shaders on average only give about 3-5% on a good day at identical clocks. There have already been reviews on this documenting quite clearly that the clocks make the real difference. I would even be willing to show you real life benches with my spare 6950 2GB reference card.

I suggest doing further research before giving people bad info

Oh side note: gtx 480 has faster RAM / wider bus. You can't just directly compare them clock for clock, even if the 470 had the same amount of shaders the 480 would still be faster. Let's also not forget CUDA cores are COMPLETELY different architecture from AMD's shaders.

 

[Outback Bronze]

Not much support for 6770, so here is australia i can get a 6770 for $99 brand new so two equals $198. The cheapest 2GB 6950 is $285 and 1GB $238. Me i like seeing two card setups as they look the part but by saying that i would still opt for the 2GB 6950. Gees i could get tri fire 6770s for $297. That would be worth thinkn about over one 2 Gb 6950!

 

[Soup]

Alright. 6950 it is.

Thanks guys (and gals?)

 

[Athlon2K15]

for sure 6950 FTW. good choice

 

[quilciri]

Bah, late to the party, but allow me to disagree a bit.

A pair of 6770's perfoms almost as well as a 6970, and certainly better than a 6950 (unless it's been modded and oc'd to a 6970, of course)
2x6770 vs 6970

A word on power consumption (from guru 3d)
All numbers are under load

6770 - 96 watts
6950 - 154 watts
6970 - 197 watts
6990 - 350 watts

so, a pair of 6770's do take more power than a 6950, but not as much as a 6970. Given their performance is on par with a 6970, no loss there. With these numbers, I find the 6770x2 to be a huge bargain.

If you only have a 2 slot pci-e motherboard, you might spend the extra money on a faster single card solution with an eye to the future. If, however, you're buying a motherboard as well, I'd advise spend a little extra to get a 3 or 4 pci-e slot motherboard. I'm currently running 3 6770's on an Asrock 970 extreme 4. This is easily in 5970 land, and may be close to a 6990 (just in case we're not all on the same page here, 5970 > 6970) for less than $300 and it takes *less* power than a 6990 would. I dunno about the 5970, but given that the 5k series were power hogs compared to the 6k, it seems likely that 3 6770's is at least as efficient as a 5970.