Is it possible to have 3 3870's in Crossfire X?

[Atreus21]

I was looking at Foxconn's X38 board, and I saw that it had 3 pci-e x16 slots. I already have one 3870, and I thought that, since 2 3870's are currently cheaper than a single X2, maybe a 3 card solution would be neat.

However, the 3870's only have 2 connectors on the top for the crossfire connectors, so that you can only connect one card to one other card.

Does ATIMD provide for this contingency?

 

[Majic 7]

You have to have Vista to run more than two cards. XP DX9 doesn't support more than two cards. You use one connector for the first two cards using the connector furtherest to left. You connect the second and third card with second connector. The third pci-e x 16 slot is 4 electrical and I have seen a lot of posts with problems using a 16x16 slot with a 16x4 slot for regular crossfire so this could be a problem. Also I am not sure if the board supports CrossfireX (more than two Cards). The board would definitely support a 3870 and a 3870 X2 though for close to the same price as two more 3870's. I have two 3870's and driver support is still kind of iffy, getting better though.

 

[Atreus21]

Originally posted by: Majic 7
You have to have Vista to run more than two cards. XP DX9 doesn't support more than two cards. You use one connector for the first two cards using the connector furtherest to left. You connect the second and third card with second connector. The third pci-e x 16 slot is 4 electrical and I have seen a lot of posts with problems using a 16x16 slot with a 16x4 slot for regular crossfire so this could be a problem. Also I am not sure if the board supports CrossfireX (more than two Cards). The board would definitely support a 3870 and a 3870 X2 though for close to the same price as two more 3870's. I have two 3870's and driver support is still kind of iffy, getting better though.

Thanks.

 

[BAMAVOO]

What kind of problems have been seen using a 16x16 and a 16x4. That is what the IP35 has. Heck, I may be better off getting a GTS 512 and dropping the 3870, if I can't crossfire it.

 

[Majic 7]

You're welcome. Now that I think about it I'm not sure if 3870 and 3870 X2 would work in XP. I seem to remember people trying two 3870 X2's in crossfire needing Vista, but I can't remember for sure. If it's not something I am thinking about doing it fades quickly.

 

[Majic 7]

Originally posted by: BAMAVOO
What kind of problems have been seen using a 16x16 and a 16x4. That is what the IP35 has. Heck, I may be better off getting a GTS 512 and dropping the 3870, if I can't crossfire it.

Mostly problems getting crossfire to work at all. Check out the AMD Game forums, that is where I have seen most of the posts. A lot of the posters there seem easily confused but I would google for problems with that set-up before trying crossfire. My board does 8x8 and works pretty well, except for the general problems. Game support and such, haven't seen the micro-stutter that a lot of people complain about but right now I only have Oblivion (works pretty good) and the Witcher (doesn't seem to make much difference) installed.

 

[BAMAVOO]

I run Vista Ultimate, if that makes a difference. I will check out their forums.

Thanks


I love the MSI Noe2 FR though, so the HD 3870 would go long before my motherboard would

 

[Majic 7]

Just remembered seeing reviews when the cards first came out that used 16x16 + 16x4 and it worked for them.