Information on CPU bottlenecking my GPU

[pranav189]

Hi Friends, I just buyed a new graphics card which is HD 7750.Reviews have shown that this graphics card can run BF3 at ultra at about 25fps
at resolution 1920X1200 with no MSAA but FXAA set to high.My Monitor resolution is 1024x768. But when I run BF3 at ultra with no MSAA but FXAA set to high ,
I get an fps in the range of 15-20 which is very unplayable as you know least playable fps is 30 and above.My processor is AMD Phenom 9650 Quad core processor which is 2.3 Ghz Processor.
I have posted about this problem in many forums and I got answers that I shoud change my CPU.But can anyone explain me theorotically how my CPU limits the capabilities of my GPU which is nothing but bottlenecking. I have no problem
at all even if it includes some mathematical calcuations.This happens in many games. I am not able to run them maxed out. for eg. crysis, crysis:warhead etc.

My specs are as follows:
AMD Phenom 9650 quad core processor
2x2gb ddr2 ram
Samsung 500 gb hard drive
Monitor resolution: 1024*768
ASUS M2N68-AM PLUS motherboard
400W local PSU

I know I need to upgrade my CPU and for that my mobo also because my current mobo doesn't spport AM3+ socket processors which are available these days.
I supposedly will buy an AMD AMD 3.6 GHz AM3+ FX4100 Processor and for it an ASUS M5A78L-M LX Motherboard.
I'm asking this cause my HD 7750 is enough for my very low resolution of 1024*768.I just want a detailed explaination of how the CPU limits my GPU.
Thanks in advance. If you need more information , just ask.

 

[striker410]

Hi, welcome to the forums.

To detect a bottleneck, here's the best route.
To test for a GPU bottleneck, go into game settings and lower eye candy a few notches. If you see a big performance boost, you are GPU bottlenecked.

To test CPU bottlenecking, go into control panel and find power options. Somewhere in there (not sure where) there is a CPU limiter/power setting. Dial it back to around 70%. If you see a noticeable drop in FPS, you are CPU limited.

This is pretty much the best way to check.

Cheers!

 

[pranav189]

Hi, welcome to the forums.

To detect a bottleneck, here's the best route.
To test for a GPU bottleneck, go into game settings and lower eye candy a few notches. If you see a big performance boost, you are GPU bottlenecked.

To test CPU bottlenecking, go into control panel and find power options. Somewhere in there (not sure where) there is a CPU limiter/power setting. Dial it back to around 70%. If you see a noticeable drop in FPS, you are CPU limited.

This is pretty much the best way to check.

Cheers!

Thanks Striker410 for your reply. I will sure try that but i think there is a 90 percent probability that my CPU is a bottleneck as it's only 2.3 Ghz.

 

[mactronix]

Its a very technical issue but I will try and explain it as simply as possible.
The GPU is reliant on your CPU to provide it with the information it needs to render the image to your display. So very basically if your GPU is capable of rendering a frame faster than your CPU can provide the info for the next frame then you have a restriction which is what people call a "bottleneck"
There are several things that go into what actually happens depending on your hardware and settings.
Don't know if you have seen this http://www.tweakguides.com/Graphics_9.html Its worth a read.

Any questions after you have read it just ask

Mactronix

 

[farrengottu]

for limiting the processor just go into power options. type power into the start menu search for easy find.
then which ever plan you have selected, click "change plan settings" to the right of it.
click "change advanced power settings"
scroll down to "processor power management" click the little + next to it then same thing with "maximum processor rate".
and change away.

im damn sure the problem is your processor if i were in your situation i would just buy something like this mobo/processor/ram combo
http://www.newegg.com/Product/ComboDealDetails.aspx?ItemList=Combo.863014
its decent enough for games. and when you feel like you need more processor you can pop in a nice ivybridge(intel next gen). since the motherboard will support it.

another alternative is you could not play on ultra settings. i play on ultra but i have an over the top computer. i changed the settings to high and it looks pretty much the same and i went from 75 fps to 96.

 

[pranav189]

Its a very technical issue but I will try and explain it as simply as possible.
The GPU is reliant on your CPU to provide it with the information it needs to render the image to your display. So very basically if your GPU is capable of rendering a frame faster than your CPU can provide the info for the next frame then you have a restriction which is what people call a "bottleneck"
There are several things that go into what actually happens depending on your hardware and settings.
Don't know if you have seen this http://www.tweakguides.com/Graphics_9.html Its worth a read.

Any questions after you have read it just ask

Mactronix

Many Many Thanks for the info. But I wanted to know how my CPU clock speed which is 2.3 Ghz limits the processing power of my GPU.
My CPU is good when it comes to multitasking cause it's a quad core.Also, I get an irritating problem in games that my FPS does not remain stable.
In BF3 ,at low settings,the min FPS I get is 40 and max FPS I get is 120. Why is there such a big difference in FPS. I will be very happy even if my FPS is about 28-30 but it should remain stable at it.
In short, there should not be much sreen tearing. Is this happening to me cause of my CPU? I tried using Vertical sync but to no avail. The framerate doesn't remain stable and varies with a big difference.
I also tried forcing Vsync through Catalyst control Panel. But the same problem.so, i wanna ask is this the problem of my CPU?

 

[striker410]

We don't know if it's your CPU. Have you done what I suggested and tested it? We don't know your machine so it's impossible to say FOR SURE which part is causing the bottleneck. Please do the things I suggested, then come back with the results.

Clock speed is not an indicator of actual processor speed.

 

[pranav189]

We don't know if it's your CPU. Have you done what I suggested and tested it? We don't know your machine so it's impossible to say FOR SURE which part is causing the bottleneck. Please do the things I suggested, then come back with the results.

Clock speed is not an indicator of actual processor speed.

I checked but there is no such setting for limiting CPU in my control panel. can this setting be done through BIOS?

 

[tonytran]

Can someone tell me if my CPU is bottlenecking.
email me: losttony@msn.com
When i play MMO/RPG games like Allods online i get about 25fps if in a busy packed server wiht lots of players.
But if im questing somewhere quiet by myself fps is around 40 to 45 fps. Im pretty sure its the cpu cuz its outdated/old

CPU: intel core 2 Duo E8500 3.16ghz
Mobo: Gigabyte GA-EP31-DS3L
GPU: Asus ENGTX560 Ti DC/2DI/1GD5
Ram: 4gb kingston hyper X
Power:500w

 

[mohit9206]

Hi Friends, I just buyed a new graphics card which is HD 7750.Reviews have shown that this graphics card can run BF3 at ultra at about 25fps
at resolution 1920X1200 with no MSAA but FXAA set to high.My Monitor resolution is 1024x768. But when I run BF3 at ultra with no MSAA but FXAA set to high ,
I get an fps in the range of 15-20 which is very unplayable as you know least playable fps is 30 and above.My processor is AMD Phenom 9650 Quad core processor which is 2.3 Ghz Processor.
I have posted about this problem in many forums and I got answers that I shoud change my CPU.But can anyone explain me theorotically how my CPU limits the capabilities of my GPU which is nothing but bottlenecking. I have no
problem
at all even if it includes some mathematical calcuations.This happens in many games. I am not able to run them maxed out. for eg. crysis, crysis:warhead etc.

My specs are as follows:
AMD Phenom 9650 quad core processor
2x2gb ddr2 ram
Samsung 500 gb hard drive
Monitor resolution: 1024*768
ASUS M2N68-AM PLUS motherboard
400W local PSU

I know I need to upgrade my CPU and for that my mobo also because my current mobo doesn't spport AM3+ socket processors which are available these days.
I supposedly will buy an AMD AMD 3.6 GHz AM3+ FX4100 Processor and for it an ASUS M5A78L-M LX Motherboard.
I'm asking this cause my HD 7750 is enough for my very low resolution of 1024*768.I just want a detailed explaination of how the CPU limits my GPU.
Thanks in advance. If you need more information , just ask.

am sure your cpu is the bottleneck. because you play at such a low resolution there is more pressure on the cpu. so my only suggestion is overclock the cpu to atleast 3ghz . before that buy a cpu cooler and ensure your case has good airflow and then overclock your cpu. it should increase your performance

 

[djnavasv]

I have a GTX 760 2GB as well and a Athom Phenom II x6 1035T 2.6GHZ. In need for speed rivals and most wanted (2012) I get huge frame drops (Only Rivals is a headache sometimes in this sense). Does this CPU bottlenecks my GPU?