HD 7990 + HD 7970 for Tri-Fire

[BIGGRIMTIM]

With Battlefield 4 coming out soon I am looking for an effective way to upgrade. I am running 3 Dell U2410's in Eyefinity. Should I sell one of my HD 7970's and pick up a HD 7990? Now that the prices are reasonable, I am curious about Tri-Fire? BF3 runs great on my current setup. Am I asking for trouble?

Thanks.

[simroz]

If you did tri-fire a third 7970 is cheapest BUT will probably slow down on the pci-e lane (which apparently is not that big a deal but i can notice this bandwith drop with 15 monitors and softTH), depending on the mobo 2x pcie will run at x16 (amd or x58 or x79 chipset) or x8 (z77 or equivalent 1155 chipset) so a 7990 will be a bonus there, plus they are cheaper now. Still drivers are needed. The latest catalyst 13.10 beta does not mention frame pacing support for eyefinity (but yes for single screen). Benchmarks will make a difference but i dont think games will.
I usually use v-sync in games to eliminate stutter anyway. No need to upgrade for bf4, here are the sys req:

bf4 specs.jpg (91.35 KiB) Viewed 4704 times

Incidentally for tri-fire info here are 2 threads with some of my benchmark scores if you want to compare to your xfire setup:
http://www.wsgf.org/forums/viewtopic.php?f=65&t=26516
http://www.wsgf.org/forums/viewtopic.php?f=65&t=26572

***Make sure to use afterburner with a custom fan profile if you try furmark, those 7970s will get HOT***

But honestly i think 2x 7970s should be enough still for at least a year or two, probably worth sitting out of the next release (as it still will be 28nm tech i think) and wait till the 22nm tech comes out (which will provide a bigger performance jump.... hopefully)

Some games cant even use more than 2 GPUs effectively. (Skyrim)

EDIT: This website allows you to enter your pc specs and see if the game will run
http://www.game-debate.com/games/index. ... efield%204

[BIGGRIMTIM]

If you did tri-fire a third 7970 is cheapest BUT will probably slow down on the pci-e lane (which apparently is not that big a deal but i can notice this bandwith drop with 15 monitors and softTH), depending on the mobo 2x pcie will run at x16 (amd or x58 or x79 chipset) or x8 (z77 or equivalent 1155 chipset) so a 7990 will be a bonus there, plus they are cheaper now. Still drivers are needed. The latest catalyst 13.10 beta does not mention frame pacing support for eyefinity (but yes for single screen). Benchmarks will make a difference but i dont think games will.
I usually use v-sync in games to eliminate stutter anyway. No need to upgrade for bf4, here are the sys req:

bf4 specs.jpg

Incidentally for tri-fire info here are 2 threads with some of my benchmark scores if you want to compare to your xfire setup:
http://www.wsgf.org/forums/viewtopic.php?f=65&t=26516
http://www.wsgf.org/forums/viewtopic.php?f=65&t=26572

***Make sure to use afterburner with a custom fan profile if you try furmark, those 7970s will get HOT***

But honestly i think 2x 7970s should be enough still for at least a year or two, probably worth sitting out of the next release (as it still will be 28nm tech i think) and wait till the 22nm tech comes out (which will provide a bigger performance jump.... hopefully)

Some games cant even use more than 2 GPUs effectively. (Skyrim)

EDIT: This website allows you to enter your pc specs and see if the game will run
http://www.game-debate.com/games/index. ... efield%204

Thank you for the detailed reply. At this point I am going to stay put with my setup. We will see how the beta performs. I know they will optimize before release but it will give me a ballpark idea.