Overclocking Venice and Modding X800PRO

I now have a P4 1.8 o/c to 2.6G with Radeon 9500 softmodded to 9700.
The upgrade bug just bite so now I’m looking at this AMD combo

MSI Neo4-F with Nforce4-Ultra Chip
AMD Athlon 64 3000+ (1.8G) Venice core
ATI Redeon X800PRO 256mb PCIe

Looks like I can safely O/C the Venice to 2.5G at least or beyond and
softmod the X800PRO to X800XT by opening up the 4 disabled pipelines.

Assuming I can achieve the above, roughly how much faster will my new
rig be comparing to my old and reliable P4 2.6G with Radeon 9700.

The reason I’m asking is that I don’t think the new rig will be too
much faster in general applications like web browsing. Of course
it’ll be faster for games but my old rig is still performing admirably
in Battlefield 2 with 30FPS in 1024x768, I just couldn’t turn any AA
or AF on.

The other game I play a lot is C&C Generals Zero Hour online and I
doubt the new rig will be too much of an improvement since it’s such
an old game.

The faster cpu will help a lot in the up and coming Civ4 which I
surely will be playing a lot.

So after shelling out $600 for the new combo, what I will get in
return is being able to turn on some eye candies in BF2 and playing
Civ4 faster, plus getting the satisfaction of overclocking like a
maniac which is exactly the point of all these upgrading anyway.

So I don’t know if it is worthwhile for me to go for it or to hang on
to my old rig one more year for something better to come out next
year.

Speaking of which, to date I have hung on to my P4 rig almost 3 years
without making any major modification which is a record to me. 10
years ago, I would have gone through one major overhaul every 12
months just to keep up. Now even thought my P4 is getting long in the
tooth, it still allows me to play new games like BF2.

By the way, anyone know what’s the difference between the MSI Neo4-F
and Neo4-F premium?