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View Full Version : Going from 7800gt to 8800gt on AMD 3800+


acoldone
10-30-07, 06:24 PM
I'm planning on buying a 8800gt. I currently have a 7800gt and a 3800+ dual core amd cpu overclocked to 2.5ghz. Just wondering what I can expect as far as performance increase at 1920x1200? I find "The Witcher" is a little choppy at this rez with my current setup. I heard that the gpu is currently the main determinant for performance at higher resolutions (lower rezes more cpu dependent)?

Pussik
10-30-07, 06:30 PM
CPU has small meaning in high res (1920 for example).

acoldone
10-30-07, 06:55 PM
my E6420 2.13ghz @ stock settings is the bottleneck on my system. i have too overclock it to 3ghz and above speeds so that it could keep up with the 8800GTS 320mb @stock in games like DiRT, graw2, vegas etc.

all new games now need fast processors.

But is this the case when you are running at 1920x1200? I remember not long ago seeing benchmarks that showed almost all processors at this rez running the same as far as FPS. The differences in fps showed up more when running below 1600x1200 which is something I'd like to avoid if I can. It seemed only the card made the difference (gts vs gtx for example).

I will upgrade my cpu, etc. eventually but I'm hoping I should see a big jump in FPS at 1920x1200 by switching out my 7800gt for the 8800gt.

SeriTonin
10-30-07, 07:44 PM
The problem is, while yes, you will see a BIG jump in most scene's, a lot of game's are still, regardless to resolution, going to be cpu based in certain scene's, especially those with a lot of physics.

Your cpu seems decent though. It's dual-core and oc'd and I agree, a gpu is in place ahead of cpu in your case. Just don't wait too long.

You'll notice while for the most part it runs well, certain spots that dropped before, still drop, thanks to the cpu. Luckily, that shouldn't be too often, as long as you can handle a few dips in frames here and there.

Airbrushkid
10-30-07, 08:15 PM
zero what res you running Graw 2 at? My system is below and I get about 65 to 80 fps. I'm running the res at 1280x960 everything high.

jolle
10-30-07, 08:42 PM
An easy way of illustrating CPU bottlenecking is for example if your CPU can push about 50 fps in a game (determined by AI, physics and other game logic).
And you GPU can push (determined by polycount, shader intensity, texture load etc)
100 fps at 1024
80 fps at 1280
50 fps at 1600
25 fps at 1920
(just examples, very broad generalization and not based on anything real)

Well, that means that in every case you will be running 50fps at most.
Until you hit a high enough resolution where the GPU becomes the bottleneck and the framerate will dip further.
In realworld situations the load shifts alot tho, so a weaker CPU will run into heavy dips more frequent when something very CPU intensive happens, and other time the GPU will get totally bogged down by heavy action.

So its true that to get the most out of a new GPU you should have a decent enough CPU to keep up the pace.
Ive ordered a 8800GT myself, cant afford a CPU upgrade (which entails mobo and RAM aswell) for a while.
Hopefully new games will utilize multithreading enough to allow this tired on X2 3800+ to distribute the load a little atleast.

Moo
10-30-07, 08:54 PM
CPU has small meaning in high res (1920 for example).

Does "pussik" mean anything in Polish? :o