AMD 6790's Crossfire setup?

[jacktesterson]

I just noticed newegg has 6790s now for $129 with $30 mail in rebates....

the performance is 90% + of 6850s in crossfire, and almost equal when overclocked.

I'm surprised more people are not using them.

I am building a new rig right now, and decided to go with the 6790's over the 6850's to save some cash. As stated in another thread, I had lost my job and sold my big gaming rig... (2500k @ 4.5 with 2x 560 Ti)... Now that I've had a great new job for a couple months, I'm getting a new gaming rig... and my GPU budget just isn't as high as I'd like. From all the research I did.... I think I made the right choice for 1080p gaming.

Mind you the Rebates are 1 per household, but I bought 1 XFX and 1 Powercolor so I could use both rebates.

this is on newegg.ca BTW.

 

[OCGuy]

I would buy a stronger card rather than multi. If Xfire isnt working correctly, you have a 6790....which I wouldnt get near if I could avoid it.

 

[Slufa111]

SLI GTX 460 1GB has better performance.

Out performs a GTX 580 in some tests.

 

[Vesku]

I did similar with the ~$130 5830s, unfortunately, even with the latest drivers it's all about which games have crossfire profiles. Alpha Strike is just visually off for me when running Crossfire. If it has a profile though it's usually excellent and AMD has stepped up their profile creation apparently.

The 5830 got a lot of flak when it came out for being a bit of a power hog and a bit too pricey but just like your 6790s it can become a great cost-performance pair up once the price starts dropping.

 

[jacktesterson]

Thats just it. How many major title games, which is what I basically play, don't work well with Crossfire or SLI (dual card mode) ? I don't see many...

 

[jacktesterson]

SLI GTX 460 1GB has better performance.

Out performs a GTX 580 in some tests.

So does a 6790 CF Setup ...Check this out:

http://forums.anandtech.com/showthread.php?t=2157093



The 6790's only require 1 6pin power cord too.

 

[trollolo]

what i've heard is that the 6790 has the bart GPU from the 6800 series, and with some overclocking is equal to them in performance

 

[jacktesterson]

what i've heard is that the 6790 has the bart GPU from the 6800 series, and with some overclocking is equal to them in performance

You are correct. It is a bart core. It's basically a 6850 with 800 shaders instead of 960. The core and memory speeds are almost identical. The 6790 requires a single 6 pin power plug, the 6850 takes two.

 

[trollolo]

i got some spare shaders in my closet you want em?

 

[jacktesterson]

Will micro stuttering be an issue? I am still in the air about this decision

 

[ZipSpeed]

Too many variables with multi-GPUs. I'm in the camp where you buy the most powerful card you can afford.

 

[jacktesterson]

Too many variables with multi-GPUs. I'm in the camp where you buy the most powerful card you can afford.

I've gone crossfire or SLI in my last 3 dedicated gaming rigs.. and have yet to experience any issues.

I'm still wondering where these issues are? Not being smart, I'd really like to know cause I've never seen any in my experience with 470's, 560 Ti's and 6950's

 

[Vesku]

Will micro stuttering be an issue? I am still in the air about this decision

Well it really annoyed me playing Alpha Strike, to the point where I disable Crossfire for it, but it was quite smooth for me playing Deus Ex: HR. There is a lot of individual variation in vision tolerance regarding things like FPS and stuttering. Is there any way you can try out Crossfire before plunking down on your own gpu pair?

Edit: if you were fine with x-fired 6950s then I'm sure you'd be fine with a 6790 setup.

 

[jacktesterson]

Well it really annoyed me playing Alpha Strike, to the point where I disable Crossfire for it, but it was quite smooth for me playing Deus Ex: HR. There is a lot of individual variation in vision tolerance regarding things like FPS and stuttering. Is there any way you can try out Crossfire before plunking down on your own gpu pair?

I'm not new to crossfire or SLI. I've owned 3 rigs more powerful then the one I'm building now... all with SLI or Crossfire setups.

Its never bothered me before, but I had used stronger cards.

 

[jacktesterson]

delete...

 

[Vesku]

Main question would be how well that 1GB of RAM will do for the next couple of years of gaming? Might be better off buying a single 6950 2GB now and Crossfiring again when you can grab a second.

 

[jacktesterson]

Main question would be how well that 1GB of RAM will do for the next couple of years of gaming? Might be better off buying a single 6950 2GB now and Crossfiring again when you can grab a second.

This is what I'm thinking too. I'd like keep this rig around for a couple generations.

I might go back to the 560 Ti, I really liked that card. Or try to find a used 570

 

[Vesku]

Do the 560 Ti's come with more than 1GB ram as standard? 570 has 1280 or some such, correct?

 

[notty22]

Some 6790's do use 2 6-pin plugs. They also come o/c higher than stock 6850's to make the stock performance difference not seem so bad, but it takes away your potential o/c headroom.
The biggest hardware negative with the 6790 is it's cut down to 16-ROP's, from 32, on the 6850,6870, 5850.
And the texture units are down to 40 from 56 on the 6870.
So the SP's are just part of what's cut down.

6850's would be better to consider imo.

 

[jacktesterson]

Well, just got the tracking info. I decided I am going to give the 6790's a spin!

Hopefully it works out. If not, can always upgrade later. For $200 I think I'll be happy for most part.

 

[trollolo]

so why the heck do graphics cards need dedicated RAM? if i have enough of the regular kind can't they just share?

 

[SunnyD]

so why the heck do graphics cards need dedicated RAM? if i have enough of the regular kind can't they just share?

/epic facepalm

 

[jacktesterson]

http://www.kitguru.net/components/graphic-cards/zardon/sapphire-hd6790-crossfirex-review/20/

Minimums in the few games they tested are better than a 2GB 6970, and Maximums close to a 580, or better than a 570 most of the time.

I'm curious. Guess we'll see how it goes.

 

[jacktesterson]

Decided to keep the 1035T for now and upgrade everything else, and wait for Bulldozer.

I'll buy a FX-8150 or 8120 when they arrive. I've used AMD CPU's for years.

Will update how the 6790's later this week.

 

[Arzachel]

so why the heck do graphics cards need dedicated RAM? if i have enough of the regular kind can't they just share?

GDDR5 has around ~8x the bandwith of DDR3, but has higher latencies if I remember correctly.