Two 5870HD cards - 1 with 1GB and 1 with 2GB

Milkman00

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So I read the FAQ, and it says that it can be done, but basically the 2GB model will become 1GB. Here is my question:

Is it worth it?? At the end of the day I will still have the same amount of video memory, but I will have 2 GPUs. Should I do it?
 

nordlead

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You don't have the same amount of VRAM, you have less. Each card will work with 1GB and it is not shared since each card needs their own copy of the graphics.

However, unless you are running extremely high resolutions that 2nd GB was never used in the first place. So Crossfire away.
 
he would have the same amount of Vram xfiring going down to 2 gb as he would with the single 2gb card. OP was wondering if the downscale with the xfire and not getting the full 3gb was worth it to have a 2nd gpu. I say yes go for it that setup will last you a long time.
 


Wrong. He'd have 2gb with the single 5870 2gb card, but if he crossfire's the 1gb card with the 2gb card, he will have 1gb total. The cards do not add VRAM in CFX or SLI! They pick the lowest common RAM amount, and both cards will have identical files in each card's VRAM. It is all duplicated exactly. Like a redundant RAID 1 HDD setup.

OP: If you can get two 2gb cards that would of course be awesome, but definitely with CFX 1gb 5870s you'll still have awesome performance and will max any game at 1080p anyway so I'd say go ahead and do that as your best upgrade option.
 

i didnt mean 2gb as a whole, but 1 per card, sorry for the confusion, i saw how that looked horribly wrong
1gb per card is still more than enough
 

nordlead

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Yea, that is why I said each card would work with 1GB (maybe not the best wording, but whatever). And yes, I do agree that 1GB is more than enough except in special circumstances. But since the OP didn't provide a resolution I'm going to guess he is running something like 1080p or 1680x1050.
 

Milkman00

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Thanks for all of the replies. I am really angry about this card. I bought it like 6 months ago, and thought it was right. Ultimately I may see about getting the 2GB version, but for now.... @%@#%@#%$.

Here are some additional questions:
■I am running 1920x1080, is that going to be a problem with only 1GB and 2 GPUs (running most games on MAX settings)
■Is it possible to run 3 monitors across 2 cards in a crossfire configuration?
■What is that small connector about on the external connector side of the card
■If I do get another 2GB card, does it have to be the exact same brand, or any brand 5870 with 2GB of memory will run perfect?

Thanks guys
 
any brand will work as long as the gpu is from the same family (5870 or 5850)
your res is fine to max anything with that xfire setup.
are you talking about the xfire brindge? the external connector is what the crossfire bridge goes on so your gpu's can work in tandem with each other.
im sure you can run 3 monitors with your 2 card setup but remember that performance will suffer a bit
the 1gb per card is more than enough
 
I'd say 1gb is enough for 1080p, but if you end up wanting to go with 3 monitors I would definitely recommend looking for another 2gb card. As Flint said, they do not need to be the same brand but I would recommend that if they have different clocks, you overclock one to make them identical.
 
I've heard different stories. I don't know for sure what's right, but the most logical thing I heard is that they clock to whichever is the Master card (first slot).

However, when I was doing a lot of overclocking on my GPUs, I accidentally ran the 2nd gpu at higher mem clocks than the first and it held for the FurMark tests. Might be because I set it in Afterburner, which is different than running at stock.