To answer your question, IMO the 4000 is definitely worth more in gaming than the 4200. The 4200 would only help you in Handling multi-task operations. It would also help you get 77FPS in MS word.
But why not save even more money and purchase the 3700? It has the same amount of L2 cache and the Speed could be made up through overclocking. It's significantly cheaper and is reported to reach 2.8 with a decent upgrade on air cooling. Just a thought.
My specs:
Antec P180
Antec TP2 550w
OCZ El Plat Rev 2 512 (2)
AMD Athlon 64 3700 - Testing OC>>2.7
Thermalright SI-120 - AS5
XFX 7800GTX (490-1300) :twisted:
DFI Lanparty NF4 Ultra D
2 Seagate Barracuda 7200.7 80GB RAID 0
Delta High Performance Fans for XFX and AMD
Klipsh 2.1 THX speakers 8)