Question about crossfire

Status
Not open for further replies.

RDS1220

Solid State Member
Messages
19
I was looking at getting a Gigabyte z68 mobo for my new board. While reading up on it I saw that it says one gpu will run at 16X speed. In crossfire mode though one card will run at 16x and the other will automatically default to 8X even though its in a 16Xpcie slot. So my question is how much of a difference does that make. Its 50% slower so whats the point of using crossfire if one card is running at 8x speed and the other at 16X. Also is that 8x default on all mobo's using a crossfire config or just z68's?
 
that is on all boards, that is perfectly normal, what gpu do you have ? because u may get a better gpu rather than buying a extra one.
 
If it is a new build then I'm with David, get the best GPU you can afford instead of buying 2 cheaper ones.
Though I'm assuming this is for future reference for if you ever want to run 2 cards?

Most motherboards actually default to x8/x8 in SLi/Xfire unless you are buying a high-end board.
As to the difference, here is a good thread on it: HARDOCP - Conclusion - GTX 480 SLI PCIe Bandwidth Perf. - x16/x16 vs. x8/x8
It seems that at 2560x1600, even with 4X AA, there was absolutely no difference between x16/x16 and x8/x8. This is good news if you game at x8/x8 on a single display configuration at 2560x1600 and below. You simply are not missing anything, and moving up to x16/x8 or x16/x16 will yield no performance improvements or gameplay differences, even on the fastest GTX 480 SLI.

However, if you game in a triple display setup at 5760x1200 or higher, then you might want to aim for more PCIe bandwidth. It seems that you will at least want your primary video card to be running at x16 mode. At x8/x8 we found "benchmarkable" differences in performance. We say "benchmarkable" because these differences were only noticed on a graph.
 
"Though I'm assuming this is for future reference for if you ever want to run 2 cards?"

Yes. Its more for if I decide to go down that road in the next couple months or year. Right now I'm willing to spend $350+ on a gpu but I don't have the money to spend 500, 600 or more on something like a 6990 or a GTX 590. So the best I can do is something like the 6970 for now and then hopefully double them up in the next couple months to year.

EDIT* just read that website and it was what I was looking for. I plan on only do one monitor for now and so if I'm reading it right and understanding it right it seems like in 16x-8X or 8x-8x there won't be to much performance lost. The biggest thing is if you do eyefinity then you can have some performce lost.
 
Just thought of something else. Lets say I got a 6970 now and installed the video drivers. Six months down the road I decide to double it up and do crossfire. Do I have to uninstall the drivers I already downloaded then re-install them to make both gpu's work or can you just lock the new video card in, setup crossfire and go?
 
Thanks but here's my problem. COD in a 64bit setup is kind of screwy. It only works with AMD 10.4 and 10.5 drivers. What I'm worried about is that I'll have compatablity problems and performance problems using a high-end card with old drivers.
 
Opps yea I forgot about that. I play pretty much all of them WOW, MW and UO. UO though needs 10.4/10.5 drivers. Also I play COH, and BF. I don't know why but when you try the 11.X series in UO it just won't work you get corruption message. I would like to use the 11.x series for the other games but then UO won't work. So I use the 10.5 drivers and UO works and so do all the other games but its just old s***ty drivers.
 
Status
Not open for further replies.
Back
Top Bottom