Crossfire question

[Liver]

I have been reading about crossfire at the ATI webpage and wanted to confirm my take on it.

I am thinking about building a new computer, but want to do it in stages and get the most for my money.

I was looking at the (as of yet) unavailable DFI motherboard and the x800GTO^2 (unlocked and overclocked to x850xtpe). Or, in the same line, use ANY x800 series card (pci-e of course).

In the future could I put in a x1800 series card (when available) and have it crossfire enabled?

Or would I be stuck with using another x800 x850 series card?

Ideally I would like to have the x800 GTO^2 unlocked over clocked, AMD X2 3800 (overclocked) and then put in a x1800 series in the future.

Is that correct? Am I missing something (aside from availability)?

Liver

 

[nRollo]

Originally posted by: Liver
I have been reading about crossfire at the ATI webpage and wanted to confirm my take on it.

I am thinking about building a new computer, but want to do it in stages and get the most for my money.

I was looking at the (as of yet) unavailable DFI motherboard and the x800GTO^2 (unlocked and overclocked to x850xtpe). Or, in the same line, use ANY x800 series card (pci-e of course).

In the future could I put in a x1800 series card (when available) and have it crossfire enabled?

Or would I be stuck with using another x800 x850 series card?

Ideally I would like to have the x800 GTO^2 unlocked over clocked, AMD X2 3800 (overclocked) and then put in a x1800 series in the future.

Is that correct? Am I missing something (aside from availability)?

Liver

Sorry dude, no mixing X800x with X1800s.

 

[johnnqq]

umm i hate to say this but rollo yo'ure wrong. you can mix any crossfire card with any x800 or above card. the only catch is that the faster card runs at the speed or at the pipelines (can't remember) as the slow card. ie- x800 pro and an x850xt crossfire edition. both run at 12 pipes i think.

basically it's not much of an advantage over sli.

 

[Liver]

I would go with nVidia's SLI with 7800GTX (one now and then another later), but I can not justify the expense of a single 7800 series right now. I have the cash, but can not justify spending it yet.

I am not a true hard core gamer, but like the games. I play WoW and occasionally fire up HL2. Currently I have no gaming computer.

I wanted to get something that will play WoW and such at 1920x1200 (Dell 2405), and if I needed more GPU power in the future I would have the option of dropping in the new series card.

Cost effective for me.

 

[nRollo]

Originally posted by: johnnqq
umm i hate to say this but rollo yo'ure wrong. you can mix any crossfire card with any x800 or above card. the only catch is that the faster card runs at the speed or at the pipelines (can't remember) as the slow card. ie- x800 pro and an x850xt crossfire edition. both run at 12 pipes i think.

basically it's not much of an advantage over sli.

I'm not wrong this time johnnqq-

http://www.anandtech.com/video/showdoc.aspx?i=2432&p=10

You can't even mix X800s, let alone X1800s. (AFAIK)

 

[lifeguard1999]

"In order to make up for their lack of a chip-to-chip interconnect, ATI includes a Compositing Engine chip on their CrossFire card. Because of this, the CrossFire card can be paired with any Radeon X800 or X850 (there will be a CrossFire card for each flavor). The driver controls clock speeds of each card automatically and manages synchronization as necessary. Synchronizing boards can be done on a general scale and doesn't need to be clock for clock. All CrossFire cards have 16 pixel pipelines, but disable 4 pipelines when running in tandem with a 12 pipe Radeon. This is what allows ATI to provide a limited number of CrossFire cards to work with multiple Radeons. Each card does need its own x16 PCI Express slot, and the boards communicate through an external cable."

Original AT preview of xFire

Confused yet? That is from the same article that Rollo quotes. I believe what they mean is that the xFire cards will work with any cards of the same type (xFire x800 with any x800XTPE/XT/XL/Pro for example) but not with cards of different types (x800 with x850).

ATI's point was that NVidia was limited in their SLI (at the time) to using the same card with the same BIOS.

 

[RampantAndroid]

well,the other prblem, is if you mix a higher end card with a lower end card that is clocked slower, the higher end card drops its performance to match the lower end card.

You're just as well off using SLI with two identical cards....

 

[RampantAndroid]

aha....another article...

linky

 

[nitromullet]

Originally posted by: Liver
I would go with nVidia's SLI with 7800GTX (one now and then another later), but I can not justify the expense of a single 7800 series right now. I have the cash, but can not justify spending it yet.

I am not a true hard core gamer, but like the games. I play WoW and occasionally fire up HL2. Currently I have no gaming computer.

I wanted to get something that will play WoW and such at 1920x1200 (Dell 2405), and if I needed more GPU power in the future I would have the option of dropping in the new series card.

Cost effective for me.

Right now if I was building a new high performance rig and was willing to sink a bit of money into it, but still wanted a decent bang:buck ratio, I'd go with SLI'ed 7800GT's. Most of the GTO2's are going for around $250ish, and you can get a 7800GT for right about $300.

http://www.tigerdirect.com/applications...details.asp?EdpNo=1549681&Sku=B52-1030

The GT is going to give you better performance right out of the box than an unlocked/overclocked X800GTO2, and will most likely still have a bit of room to OC if you wanted to do that.

 

[Fadey]

Get sli , nvidia 7800's in sli x16 with TSAA looks alot better than the x14 from crossfire.. http://hardocp.com/image.html?image=MTEyNzA5NDc4MmdGVFFiWW1Ybk1fNF80X2wuanBn

 

[Steelski]

Originally posted by: Fadey
Get sli , nvidia 7800's in sli x16 with TSAA looks alot better than the x14 from crossfire.. http://hardocp.com/image.html?image=MTEyNzA5NDc4MmdGVFFiWW1Ybk1fNF80X2wuanBn

That is SLI with Temperal AA on is it not?
If it is not then hands down but i think it is.

http://hardocp.com/image.html?image=MTEyNzA5NDc4MmdGVFFiWW1Ybk1fNF8xX2wuanBn
This is from the same article and shows the 14AA doing a better job on the powerlines.
I would guess that if the ATI cards had AAA enabled it would be a different story in the pictures you showed.
Speaking of witch, i cant wait for some rwal SLI GTX comparisons for Xfire X1800XL/XT.