I'm looking to upgrade my current system to get more processing performance, hopefully with little more effort and cost than upgrading the processor. Upgrading the motherboard is an option but not a preferable one. I currently have: HP Pavilion a1540n Desktop PC - Product number Ex276AA Athlon 64 X2(W) 4200+ 2.0 GHz 2000 MT/s Socket 939 GeForce 6150 (But am using separate GeForce 7600 GS that's adequate for my graphics needs. Asus Motherboard A8M2N-LA (HP NodusM-GL8E) 4 GB Ram (of which Win XP can only use 3.5 GB) 240 pin DDR2 SDRAM 250 GB SATA @ 7200 RPM So..... Is there a better processor I can swap in for a significant bigger bang with a few bucks? Is there an opportunity to get a vastly greater boost with a motherboard swap? How vast? Is there reason to get over my overclocking shyness and consider that route? Thanks!