Um it doesn't matter long as you can play those games smoothly but I will try to answer your question. Whats the biggest monitor you got? Trying playing HL2 at the lowest res with lowest quality textures and then higher quality textures, then up the resolution (first do low quality textures all up to 1600X1200 then do the test again but with high quality textures) and see if your frame rates are about the same. If your frame rates only drop a few points then you know the CPU is bottlenecking, go up to how ever high resolution you can and when you notice a very deep drop in frames, then you will know where the GPU is bottlenecking. If the frame rates are consistant up to 1600X1200 then it's most definately the CPU is the bottleneck.
I heard lately that GPUs are so powerful (mostly the 6800Ultra and X800 series) cards are being bottlenecked by the CPU up through 1280X1024. In your case (I have your card) I think you might have a pretty even combination, I don't think either are bottlenecking the other one. So in other words I don't see a bottle neck. I haven't run my system at default speeds for such a long time I can barely remember HOW much BETTER my frame rates were when I overclocked the computer to where it is in my sig (before video overclock). I remember it was significant though but that could be attributed to the FSB. And since your system is overclocked as well, I think it's even MORE likely that they are paired up.
I've run a ATI Rage 128 Pro on a 1GHZ system from a 450MHZ system and the score doubled! (458 to 906 3D Mark 2001 score). But when I put that card in a dell 1.7GHZ system the score stayed perfectly the same, showing you what was clearly the bottleneck. Here is a clue, I benchmarked the R9800Pro in the Dell 1.7GHZ system and got a 3D Mark score of about 11K, put the card in my current system in sig with defaut speeds and got a score of 17311. Overclocked the CPU and got 20K on my 3D Mark score so you do the deciding from there to what would be a bottleneck.
