Phenom 955 + 2x5770 CF = microstutter due to bottleneck?

[gravitybear]

So this might sound like a slightly noobish question, but I couldn't find a specific answer anywhere, just vague references. My overarching question is: Can a CPU bottleneck cause microstuttering in games? And more specifically, should my CPU be able to handle my CF (5770s) without bottleneck, specifically in BF3?

Sys specs:

AMD Phenom II X4 955 Black Edition Deneb 3.2GHz
2x saphire radeon 5770
MSI 790X-G45 AM3 AMD 790X ATX AMD Motherboard Socket AM3
Crucial 8GB 240-Pin DDR3 SDRAM DDR3 1066
Microsoft Windows 7

I'm running 11.10 CAP 4 drivers, which eliminated some of worst microstuttering I was experiencing in BF3, but not all. When I run a single 5770 and play BF3, all 4 processor cores stay around 80-85% load and there is no microstutter. When I use my 2x 5770s, the cores stay between 95-100%.

Since 11.10 and CAP 4 solved a lot of the microstutter, I'm thinking that the actual CF issue was resolved, and now the microstuttering is coming from my processor not being able to handle the 5770s in crossfire in a graphically intense game. Is that accurate? Should my CPU be totally maxed when running BF3 in crossfire? If so could that be causing the issue? Would an overclock to 3.6 or 3.8 help, or should I even bother?

Thanks in advance!

 

[FinneousPJ]

You get microstutter because you have two lower end GPUs. It's not a CPU issue. Had you asked I'd have recommended a single GPU setup over 5770 CF any day.

 

[inerax]

I have the same CPU with dual 6950's. i run BF3 on ultra with no stutter or lag at all.

i am running the newest beta drivers. i dont know if thats the same as 11.10 or not.

 

[gravitybear]

normally I would agree with you but I have no microstutter on a single card on the same settings. Only on 2 cards. So the question is: is it still CF causing the stutter, or is the processor load causing the stutter because it is higher using CF?


I also have had this setup for a year with no noted other problems.

 

[GhislainG]

Microstutter can't occur unless you run In Crossfire or SLI mode.

 

[FinneousPJ]

Let me reiterate: it is not recommended to CF with lower-end GPUs. It's better to buy a single more powerful card up to about $300-$400. Some people swear 6850 CF is great but IIRC the Tom's article didn't agree 100%.

 

[gravitybear]

Let me reiterate: it is not recommended to CF with lower-end GPUs. It's better to buy a single more powerful card up to about $300-$400. Some people swear 6850 CF is great but IIRC the Tom's article didn't agree 100%.

dude I'm not disagreeing with you. I will probably never buy CF again. But since this is the setup that I have, I just want to isolate the source of the problem. Not looking for purchasing advice as I don't want to buy anything right now.

 

[gravitybear]

Microstutter can't occur unless you run In Crossfire or SLI mode.

ok thanks, so a CPU on high load cannot cause microstutter? Only FPS drops?

 

[FinneousPJ]

dude I'm not disagreeing with you. I will probably never buy CF again. But since this is the setup that I have, I just want to isolate the source of the problem. Not looking for purchasing advice as I don't want to buy anything right now.

Refer to my first post

 

[vitornob]

CF and SLI causes the microstuttering, it's a intrinsic non-isolable problem originated by the very nature of how CF and SLI works.

 

[gravitybear]

thanks dudes.. sounds like I will never buy CF again. Hope AMD releases some more updated drivers that will resolve the issue. CAP 4 reduced it significantly but it is still there, and definitely enough to be irritating.

 

[vitornob]

Drivers updating really helps to minimize it, but can't eliminated it at all.
Sad, but I suffer from it too

 

[GhislainG]

ok thanks, so a CPU on high load cannot cause microstutter? Only FPS drops?

That's not totally correct. Installing a third 5770 should decrease microstuttering as long as the FPS is high enough. Did you read http://www.tomshardware.com/reviews/radeon-geforce-stutter-crossfire,2995-6.html before buying a second 5770?

Unfortunately people sometimes recommend to buy a less expensive graphics card and then add a second one later on. This is fine only for people who don't notice or aren't bothered by microstuttering.

 

[rds1220]

Will you still get micro stuttering with two high-end video cards in SLI or Crossfire? If so then whats the point? Whats the point of spending all that money on two video cards for more performance only to get stuttering and other problems?

 

[gravitybear]

Will you still get micro stuttering with two high-end video cards in SLI or Crossfire? If so then whats the point? Whats the point of spending all that money on two video cards for more performance only to get stuttering and other problems?

I've been reading lots of threads where the owners have 6970s or 6950s and getting stuttering, so it seems like the answer is yes. Which is why I won't ever be doing CF again.

 

[gnomio]

Do you have v-sync enabled?

 

[gravitybear]

That's not totally correct. Installing a third 5770 should decrease microstuttering as long as the FPS is high enough. Did you read http://www.tomshardware.com/reviews/radeon-geforce-stutter-crossfire,2995-6.html before buying a second 5770?

Unfortunately people sometimes recommend to buy a less expensive graphics card and then add a second one later on. This is fine only for people who don't notice or aren't bothered by microstuttering.

Well, I bought the second 5770 a year ago after the price dropped, and I did read a lot of reviews before I did, including the CF review on toms about 5770 xfire. And everything has been actually great since I did, absolutely no micro stuttering at all and greatly increased performance. BFBC2 works fine, the witcher and witcher 2 work fine, crysis works fine, sc2 works fine, oblivion, fallout and fallout NV work fine, all my old games like CSS work fine too. So it seemed like I made an OK decision for the past year. But BF3 can be almost unplayable sometimes, and I can't decide if its a function of BF3 being more demanding than any of those games (but bfbc2 is pretty demanding) or what.

Anyway, I also found this thread with a few more things I need to try in case anyone else is interested:

http://www.overclock.net/ati-drivers-overclocking-software/1151112-battlefield-3-crossfire-issues-complete-list.html

But yeah, I probably won't do CF again because it doesn't seem worth it if you are spending $400 or less.

 

[rds1220]

So again I can't see the point of buying two high-end videocards like a 6970-6990 or a GTX 570-580 for better performance only to have a lack of pure performace.

 

[gravitybear]

Do you have v-sync enabled?

I vsync'd and triple buffered and it stuttered, so I just turned it back off. I like screen tearing it means I'm getting the max frames possible

 

[gravitybear]

So again I can't see the point of buying two high-end videocards like a 6970-6990 or a GTX 570-580 for better performance only to have a lack of pure performace.

yep exactly, it's not like a 6970 is lacking for power... I mean you can run bf3 1920x1080 ultra everything with probably 4x or 8x AA.

 

[gravitybear]

Best answer selected by gravitybear.