CPU vs Graphics Card

Some games are more CPU dependant than others (Unreal engines usually use more CPU power than, say, Quake engines), but generally the GPU is king of the processing where games are concerned. The CPU will be doing calculations such as the physics / in game AI etc.. and as such does affect game performance but not in the same way that the GPU does.

Texture detail is dependant on memory (larger textures = more memory required) and if the engine makes full use of the AGP port to utilise system RAM for textures as well as the memory on the video card then the CPU and mobo would have much more work to do.

To give you an idea, I would say that most of todays games would work just as well on a top end Pentium III with the best GPU you could buy as they would on a P4 with the same card. Before I get flamed, I do accept that the frame rates would be higher on the P4 but not more playable. AFter all when we see 300 fps on Quake 3 it is meaningless - once you have got past 60 fps you cannot get any smoother for gameplay than that.

In terms of your system performance, you would notice a bigger difference in Windows / Desktop mode by upgrading the CPU because that normally goes hand in hand with a new mobo and faster memory - ie the whole subsystem is faster at every level.

For gaming though, the GPU will give you the best gains with an upgrade. There are some situations where your CPU could be so old that it actually limits the game no matter what video card you have but this is unlikely as most newer games have a higher minimum requirement in the CPU bracket anyway.

For overall system performance, an average CPU and video card will be a better bet than a great CPU and poor GPU or vica versa. So for example an FX5600 coupled to a P4 2.4 would be better than a 600MHz Celeron coupled with a Radeon 9800XT.

In the end it is all based on your what you will mostly use your PC for.

4.77MHz to 4.0GHz in 10 years. Imagine the space year 2020  

Generally...

AA, AF, hardcoded directX effects and shader effects, and texture size that can be held in video card memory are GPU dependant.

Artificial intelligence is always CPU dependant. Texture size is also dependant on your CPU/memory/hard disk if it can't all fit into video card memory. The size of the game level and the memory it takes is also CPU/memory/hard disk dependant.

It also varies alot depending on the game in question and how it is coded, but these generalizations usually hold true.

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<b>Radeon <font color=red>9500 PRO</b></font color=red> <i>(hardmodded 9500, o/c 340/310)</i>
<b>AthlonXP <font color=red>~2750+</b></font color=red> <i>(2400+ @2.2Ghz)</i>
<b>3dMark03: <font color=red>4,055</b>

All I know is when I upgraded my cpu from 1.5willimette with pc133sdram to a 2.66ghz northwood dual channel memory while retaining the same radeon9600 it made all my games much more playable. BF1942 went from around 30fps to 100fps. I dont know but I still think having the best gpu with an obsolete cpu is a waste.