buy a 6990 or 6950 crossfire - Micro stuttering?

ravine78 · 15 Oct 2011 at 18:22

Hi guys,

I am saving up for a graphics card, but i am not certain of which one to get?

question is, how much Micro stuttering does a 6990 compare to a 6950 crossfire?

I keep changing my mind from a realistic 6950 crossfire to 6990, as i think that a 6990 is better long term even if the 7000 gpu come out?

sorry if this has already been answered.

Blue160 · 15 Oct 2011 at 18:26

The 6990 is effectively running crossfire on it's own between it's two GPU's. Microstuttering should be equally likely with both setups.

schnipps · 15 Oct 2011 at 18:50

The only reason to buy a 6990 ever imo is to tri-fire it with another 69 card, other wise go seperate cards

ravine78 · 15 Oct 2011 at 18:53

schnipps said:
The only reason to buy a 6990 ever imo is to tri-fire it with another 69 card, other wise go seperate cards

i've read about this :-)

interesting, but would the 6990 have to some how match the clock speed of a 6950? sorry, i hope that makes sense?

sedmonds · 15 Oct 2011 at 18:57

ravine78 said:
i've read about this interesting, but would the 6990 have to some how match the clock speed of a 6950? sorry, i hope that makes sense?

No, doesn't have to match

ravine78 · 15 Oct 2011 at 18:59

sedmonds said:
No, doesn't have to match

so the 6950 and then a 6990 would both run at stock settings? i have an an ocz 850w psu. would that be enough?

schnipps · 15 Oct 2011 at 19:04

All run at the lowest clock and a 6990 runs slower then a 6970 clock wise anyway at 830 core and 5ghz ram, standard 6970 runs 880 core and 5.5 on the ram

ravine78 · 15 Oct 2011 at 19:07

schnipps said:
All run at the lowest clock and a 6990 runs slower then a 6970 clock wise anyway at 830 core and 5ghz ram, standard 6970 runs 880 core and 5.5 on the ram

nice, if i was to purchase a 6990 for the moment. which case would you recommend? i really like the corsair 600T. but i am open to any suggestions though.

sedmonds · 15 Oct 2011 at 19:08

850W should be enough, but can't say for sure, works okay for my 2 6950s, but a 6990+6950 probably requires more.

schnipps · 15 Oct 2011 at 19:08

Unsure on case but they are big cards, personally i have an nzxt phantom and its easily big enough, post over in the case forum.

gareth170 · 15 Oct 2011 at 19:11

ravine78 said:
so the 6950 and then a 6990 would both run at stock settings?

if msi AB is running then yes. i.e my 6950 runs at 810/1250, 6990 runs at 830/1250.

gareth170 · 15 Oct 2011 at 19:16

sedmonds said:
850W should be enough, but can't say for sure, works okay for my 2 6950s, but a 6990+6950 probably requires more.

850W would be enough for 2 6950.

u need at least 1000w for 6990+6950

JeffyB · 15 Oct 2011 at 19:21

There are a few reasons to choose the 6990 over cf6950's and visa versa. The 6990 has 2 high binned cayman chips, this allows them to run at lower voltage, produce less heat per gpu and overclock better. It's a single card solution leaving you more pci-e slots free with an upgrade path (trifire). If watercooling you need only buy 1 block. The 6990 is noisier under load, very long and costs more.

neilo66 · 15 Oct 2011 at 19:21

on the subject could you put a6990 with 2 6950's i have 3 pci slots on my motherboard could it be done?

ravine78 · 15 Oct 2011 at 19:22

neilo66 said:
on the subject could you put a6990 with 2 6950's i have 3 pci slots on my motherboard could it be done?

interesting, i was thinking about crossfire just now. but i imagine that there would need to be a fan on the side of the case directly above any crossfire?

gareth170 · 15 Oct 2011 at 19:23

neilo66 said:
on the subject could you put a6990 with 2 6950's i have 3 pci slots on my motherboard could it be done?

yeah

max is 4 gpus

ravine78 · 15 Oct 2011 at 19:26

gareth170 said:
yeah

max is 4 gpus

4 gpu's: wow, maximum electric bill - hehe

CSA · 16 Oct 2011 at 10:06

is micro stuttering still a problem these days ? ive been thinking about adding another 6950 to my rig for bf3 but remembering back to my 4850 CF days the stuttering was quite bad

Surveyor · 16 Oct 2011 at 10:49

neilo66 said:
on the subject could you put a6990 with 2 6950's i have 3 pci slots on my motherboard could it be done?

I wouldn't recommend that for 2 reasons:

1) 4 GPU's can give poor scaling compared to 2 or 3 GPU's. 3 GPU's seems to be the sweet spot with the HD 69xx cards as the 3rd GPU offers a decent performance boost and pretty much eliminates micro stuttering.

2) The third x16 PCI-E slot on your motherboard only operates at x4 speed which can reduce the performance of a GPU in that slot considerably.

ravine78 · 16 Oct 2011 at 11:40

i've decided for now anyway, that i am going to get 2 6950's in crossfire. as buying a 6990 is not only too expensive it would also use more power if i decided to buy 2 additional screens.

hopefully, 6950's will last me a long time

i have a antec 300, and two 6950's would fit inside. as opposed to a 6990 and then forking more cash for a corsair 600t.

however, i am open to any suggestions. i mean, is a 6990 better long term? even if the high end 7000 eventually come out?