You mean like these synthetic benchmarks?
Q6600 2.4GHz --> i5 2.4GHz = 20% performance bump.
Q9450 2.66GHz --> i5 2.4GHz = 5% performance bump. (Q9450 2.66GHz is roughly equivalent to a Q6600 OC@3.0GHz)
Q6600 2.4GHz --> i7 920 @ 2.66GHz = 38% performance bump.
Q9450 2.66GHz (or Q6600 @ 3.0GHz) --> i7 920 @ 2.66GHz = 25% performance bump.
So. If you got a nice heatsink and did some very minor overclocking, you could easily match an i5 for performance and get within about 20% of an i7 for 1/6th the cost.
I really wish people would tell the whole story and provide sources and numbers instead of just being a jackass and calling peoples' hardware "ancient" and sucky and outdated. Sounds like Paris Hilton doing a PC review.
Furthermore, this whole discussion of CPUs gets blown up when talking about ISBoxer. Due to the way it (usually) runs all clients at max resolution and reading the OP where they are running at 2048x1154, there is a much larger impact on VRAM and GPU than there is on CPU. Especially with the Cataclysm engine updates.
Personally, I'd look at doing a leapfrog update of the 9800 to a more recent card like a GTX 470 for about $250 which will at least _double_ or _triple_ the graphics performance of your 9800. The Q6600 is fine if you're only running 5 clients, though I would definitely try stepping the 4 alts down to 800x600 or 1024x768 or so. You really don't need to run them at max rez, IMO. Maybe there's a technical limitation (like losing the mouse broadcasting feature) with ISBoxer that necessitates that but I'd be surprised if so.
[edit] On a related note, see this page for a glaring example of how synthetic benchmarks like 3DMark can drastically skew numbers versus what you'll see in real-world game scenarios.
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