As for video cards, since when Nvidia started to beat ATI so badly?
By the way, why are AMD's CPUs slower clock by clock now?
Yeah, the 9800 Pro was great, I was even using one up until a few weeks ago. Nvidia's competition to the Radeon 9600/9700/9800 was the GeForce FX line. I think that's when Nvidia started going putting a lot of time into chipsets, and their video cards suffered. From there ATI gained ground and took the next step with the X800 which was a great card. I think Nvidia did ok with the 6800, but not enough. I loved my 7800GT, I think that's when they started winning again. However, my current card is ATI, I prefer them...But if I was going for absolute best performance with money not being a deciding factor, it would be Nvidia now.
Why are they performing worse clock per clock now? Ever since socket 478 we've been on an architecture called "Netburst". Everything from the Northwood, Prescott, Presler, all of it has been Netburst. For comparison, the Pentium-Mobile line(Centrino, for the laptops) has been a different architecture. And of course AMD has their own. Now, Netburst is gone, and we're using "Core" architecture with the Conroe and later CPUs. This new architecture performs better than AMD clock per clock, and clocks higher than AMD. Win Win.
I am no expert, but I do not think that cache can be the deciding factor when it comes to CPU power. It may effect some things, but it might just be faster to get the data you need out of the RAM. Of course it helps, but making a 32mb cache CPU wouldn't necessarily kill your competition. Also, there are heat/power problems with all that extra cache. I think it's a fine balance.
Hope my outdated two cents helped!
(look at my sig, I'm an old timer!)