How can i tell if a CPU is bottlenecked

[burrellbuzzman]

Hey, just recently bought a ati hd5850 gpu to put in my system that i built last year.

I have an e8400 and it's not overclocked so it's at 3ghz, i just wondered if this would bottleneck my hd5850?

and just in general how can you tell?

Thanks rob

 

[clement4413]

No I don't think your CPU is bottlenecking, The E8400 is still good CPU moreover I guess that you play in high resolution (1680*1050) so it's your GPU who work but your CPU will be able to be bottleneck if you play in low resolution

 

[burrellbuzzman]

thanks for the reply, i actually have a 1440x900 display would that make much difference? btw just in case you need to know my motherboard or anything it is an ga-ep-45-ud3p.

Thanks again

 

[clement4413]

1440*900 This is good, You will be CPU limited in 1024*768 or maybe 1280*1024, when you see a CPU test, you will see that games resolution are always low like 800*600 or 1024*768.

I have been a intel pentium 4 641 o/c 4.6 ghz (radbox intel) and X1950 XT 512 mo and I played in 1024*768 (15 inch monitor), it was horrible ^^

 

[Raidur]

You can try overclocking your CPU, and if you get a significant increase in performance, that means you were bottlenecked (assuming you test on a game that isn't CPU dependent, like FSX or GTA IV).

One of the ways I try is by lowering my resolution. If the FPS doesn't go up it usually means your CPU is only capable of producing that many frames, meaning it is bottlenecking.

I'd expect an E8400 to be capable of running a 5850 but a slight oc to 3.4+ wouldn't hurt. Those E8x00 CPUs beg to be overclocked, they do it so well.

Oh yeah, and you can run a 3Dmark and compare it to other users using a 5850. (Make sure you look at GPU score, as the total score brings the CPU into the equation)

 

[burrellbuzzman]

Thanks for all the replies!

i feel like a bit of a liar with some of the FPS im going to say... i had fraps on and ran battlefield bad company 2 and cod4

BFBC2@ 1024x768
first level was getting frames averaging about 50/60fps and fluctuating all the way up to 95

BFBC2@ 1440x900
again first level averaging about 40fps and fluctuating up to 75

then

CoD4@ 640x480
running around the first level near gaz ranging from 200-300fps

CoD4@ 1440x90
again running around the first level neat gaz staying at about 135fps and some times creaping up to near 300

now,

i thought that i would just stare into gaz's eyes near the first level and @640x480 got about 525fps and then @1440x900 i got about 275fps


Now i dont know, but obviously these are not proper benchmarks. these are just numbers pumped out by fraps, so what do you think? bottlenecking or not?

as for oc'ing i am a bit of a novice and a little scared lol

thanks for everyones help rob

 

[popatim]

I think we don't know. What you did is benchmark your video card. Did you monitor your cpu usage at all during these tests? If you're not pegged at 100% with cpu logging turned on then theres no way your cpu is bottlenecked.

I would like to beleive that if you're bottlenecking an e8400 then you have too much crap running in the background...

 

[Raidur]

Don't be scared, check out the overclocking section. They have a sticky just for C2D, and is quite easy once you get the hang of it.

 

[burrellbuzzman]

unfortunately i didnt monitor my cpu usage, if i ran unigine heaven benchmark (seeing as i have directx11) would that produce a log that looks at my cpu usage?

I dont think that there is too much crap running in the background, i have the standard 4gig that everyone seems to have. I remember reading an article here about windows 7 apparently using more memory than vista most of the comments said their usage of ram when running simple tasks with was about 1 gig, and thats what mine uses when doing similar tasks, so i hope there isnt too much crap running in the background!

Thanks again rob