Determine PCI Express speed of GFX card?

[boole]

Hello.

For my new system I need to run two extra displays, which means I need a second GFX card (along with the main 16x gaming card in the primary PCI Express 16x slot).

I think I can use my old 7800gtx 256mb card but I need to know what PCI Express speed it actually requires to function, as some motherboards have a secondary PCI Express 16x slot which can only operate up to 4x PCI Express link speed (which I think theoretical bandwith is 10gbps), I would like to know what the effect would be with a 7800gtx on a 4x link and how you find that required, or maximum PCI Express figure for a given card as I can't find it on nvidia, although it says designed for PCI Express 16x, I think that just means the slot, any help would be appreciated, thanks!

PS. I would not be gaming or doing any 3d stuff on the secondary card/displays, the most taxing thing would be playing a fullscreen movie.

 

[Gravemind123]

4x link is fine for older and lower end graphics cards even with 3D stuff. If you aren't using 3D then you won't even be making use of 4x speeds, so you shouldn't have any issues using it for just 2d and movies.

 

[ZOldDude]

Don't most new GFX cards support dual monitors today?
What MB do you have as most older ones ran 16X and 8X....never heard of the 2nd card running at 4X.

 

[Gravemind123]

Don't most new GFX cards support dual monitors today?
What MB do you have as most older ones ran 16X and 8X....never heard of the 2nd card running at 4X.

Intel 945, 965, 31, 33 and 35 series use a second card running at x4, and he said 2 extra monitors so I'm guessing he already has 1 or 2 that he uses with the current card.