6870x2 2gb...need advise

[latexyankee]

Hey guys first post, been lurking this forum for years always good advice here.

So I have a dilemma and some questions. All of this is for my eyefinity setup 5760x1080

I'm looking for a simple upgrade. I currently have one 6870 for eyefinity. Despite what people say, I'm actually quite pleased with the performance of this card in eyefinity. Most games run @ 45fps or better with a combination of medium/high settings. As all of you know, this card is 1gb vram. I have been wondering what is the best option now. 6870 in CF scales extremely well and would be mighty fast but still 1gb vram. How much difference in performance has anyone noticed @ this res going from 1 to 2gb? A single 6950 would be an upgrade (2gb vram) but I'm not sure if the price per performance would be worth it. $300 for 10-15%...not sure. I know everyone will say to CF 6950 and be done but that would lead to new power supply etc etc...

So here are my questions, would a single card with 2gb be a noticable upgrade over my card with 1gb. (My card is OC well so I'm sure its about as fast as 6950). Or there is this 6870x2 2gb which seems to rock, benching better than 6870 CF and up there or better than 580. i could run this card on my existing psu. But I get different information everywhere about the vram in this dual gpu. Some are saying that since its a dual gpu total 2gb that its no different than 6870 CF 1gb usable. Others are saying the design in the card is to use the total 2gb, somthing about 1 gpu rendering the odd frames and 2nd gpu rendering the even frames making the total 2gb usable. If the latter is true, is that how the 6990 is designed? 2gb per card but a total of 4gb usable? If it s a true 2gb card I may spring for it, it would be a 50% performance increase for sure. It seems a little pricey but if I dont have to buy a new psu and I sell my existing 6870 to my buddy it'll still save me a couple hundred $ over a traditional CF solution. Please leave comments or advice thanx!

 

[samuelmorris]

All Dual GPU cards require separate memory for each GPU, including the HD6990 and HD6870X2. Powercolor initially advertised the HD6870X2 as a 4GB card like the 6990 (2GB per GPU) but have since revised that to 2GB (1GB per GPU). Normally speaking, 1GB per GPU is inadequate for eyefinity. It works a lot of the time, but there will be some games where it will be completely unusable. If you want to really do it right, I'd go with two 2GB 6950s or 6970s, or a proper HD6990.

 

[latexyankee]

Then why in the reviews I'm reading are they blatantly stating "2gb ram to ensure stability in high and multi monitor configurations." Sucks. And I don't really want to do it right, I don't have "right" money. I want to do it modest.

 

[samuelmorris]

Then just get another HD6870 and have done with it? Having 1GB of video memory per card isn't ideal but it's not the end of the world, and it'll still be better than using a single card that also only has 1GB of memory.

 

[latexyankee]

Samuel let me ask you this: which do yall think would give the better boost? Another 6870 in CF, or a single 6950/6970 2gb? Remember 5760x1080...thanx

 

[samuelmorris]

Another HD6870, without question. In terms of actual rendering power, you'll only just notice the difference between an HD6870 and 2GB HD6950, even at that res it's about 15-20% difference. You'll only start to see problems with video memory when you have more raw performance, because the sort of games that use more than 1GB of video memory at that res are also going to want a lot more than a single HD6870. Ideally you'd want two 2GB HD6950s, but if that's out of the price range, as I say before, go for an additional HD6870.