AMD Radeon HD 7970 Crossfire bottleneck @ 4.5Ghz

[Jon-Doy]

I have been using AMD Radeon HD 7970 Crossfire @ 4.5Ghz and when I am playing Battlefield 3 then I am facing FPS drops, in my case I have set the details to high and not ultra where as everything else has been maxed out and have Turned off the MSAA, I have found that the fps drops to 60 when there is a lot of action on map, this happens more in Gulf Of Oman map Specially, I don’t think it is normal, as far as I know it should be 100-120FPS in that area but then they are just dropping when I am using 120Hz monitor, is there anyone who has an idea about the same and can help me out as well.

[GoutamB]

I have been using AMD Radeon HD 7970 Crossfire @ 4.5Ghz and when I am playing Battlefield 3 then I am facing FPS drops, in my case I have set the details to high and not ultra where as everything else has been maxed out and have Turned off the MSAA, I have found that the fps drops to 60 when there is a lot of action on map, this happens more in Gulf Of Oman map Specially, I don’t think it is normal, as far as I know it should be 100-120FPS in that area but then they are just dropping when I am using 120Hz monitor, is there anyone who has an idea about the same and can help me out as well.

If you are finding cpu to be at 100% usage at any point then it would be a bottle neck but then I doubt that it would be on a 120hz monitor at 1080p or above, you should monitor your cpu usage for each core with the help of hwinfo32 and then linking the stats that you get to msi afterburner from hwinfo32's config utility by using rivatuner plugin option, just check it out and then let me know what you get.

[Jon-Doy]

I have checked out the same and it is appearing to be using approx ~50% as well as 5.3GB of system memory, anyways below is the system specification:

• Videocard: HD 7970 CF@1125/1575
• Processor: 2600K@4.7Ghz
• Mainboard: Asus P8Z68 Deluxe
• Memory: Corsair XMS3 1600Mhz 16GB
• Soundcard: Asus Xonar D2X
• PSU: Corsair AX1200

[Dorkfoot]

I am not very sure but then have you tried out playing the game with HT disabled and see if it is making any difference in the fps, if you still find out that the 2600k is a bottleneck then I don’t think that you can do any much with the mainstream processor, I have found a number of people saying that Bulldozer has appeared even bigger bottleneck to them but then as you have mentioned 50% of the 2600K I doubt that there is bottleneck, anyways just run the game with HT disabled and then post back the result that you get for it.

[Jon-Doy]

Hey thanks for your interest but then I have tried disabling HT but then it is not making any difference, I am really finding it strange that the a 2600k runing 4.5ghz is bottlenecking, I have made some more troubleshooting and when I am Running one card then it is 50-70FPS area in that area and when I am using both of them then it is just going under 70FPS but then I have found that it is 70-100FPS on big maps if there is a lot of action, I just wanted to know that can it be a driver issue and so?? I have tried enabling MSAA but then the FPS seems to be dropping more, at this point the cards are clocked to 1080/1500 where as the temperature is 65-69C, is there any other workaround that I can try out???

[Haimi-32]

I really don’t think you should be getting such lows FPS as I am having the below specs and I am getting average of abt 75-80fps on max setting I am using Ultra and I have enabled 4xMsaa, I have faced drop in fps but then it has never been lower than 60fps, I think that there is some issue with the drivers, are you having the latest driver for the same. Just check out the gpu load with msi afterburner and if you are finding it below 90% when the average fps is 60fps then you might be having a cpu limit.

[Kh@LnaYak]

Even I think that it might be a cpu limit and not a driver issue, can you just check out the below settings and see if it is making any difference?

• If possible overclock your cpu to 5ghz
• Make sure that you are turning all settings to high or ultra
• Just Mesh Quality only to medium

[Simkin]

i have the EXACT same setup as OP.

i7-2600k @ 4.7Ghz
7970 CF 1125/1575
Asus P8Z68 Deluxe/GEN3
Corsair XMS3 1600Mhz 16GB
Asus Xonar D2X
Corsair AX1200W

You cant use task manager to measure cpu usage, use HWinfo. its NOT using only 50%, but each core can individually hit 90%+, i have seen it myself..

I also get this drops in BF3 that you are having, so its seems like the CPU is the bottleneck here..

One thing that improved my fps was to set Mesh Quality to Medium, everything else i run High/Ultra mix, and everything else Maxed, Blur off and 2XMSAA.. i run one 120Hz 1080p monitor.

It may also be a little bottleneck in the PCIe 2.0 lanes, at least im gonna buy IVY bridge when it comes out, as i have a GEN3 card and can take advantages of PCIe 3.0