RAM runs in realtime access on the fly. You can't "defragment" RAM. However, the software probably better manages program access to RAM addresses in XP. and why might you ask? Because XP does not directly access memory but uses a Hardware Abstraction Layer (HAL) and so I believe RAM "defrag" software must have some HAL organizational tool goin' on!
Noli Nothis Permittere Te Terere!!
EVGA 680i, Dual EVGA 8800GT'S (650/950), 4 gigs OCZ DDR2 1066, Intel Q9450 at 3.8 Ghz, Koolance Water Cooled, Dual Plextor16x DL DVD+/-RW. Dual WD 250gb 16mb Cache Sata 3.0. 3DMark06 score = 19,168.