Well to be at 1200MHz it looks like the mobile is running at 200 (400) FSB times a CPU multiplier of 6. You need to verify that your motherboard can change the multiplier then move it up to say 11 which would get you to 2200MHz (the speed of the XP3200+).
If your board doesn't support multiplier changes you'll have to use the wire trick to increase the multi.
K8N Neo2, Opteron 180, 2GB G.SKILL PC3200, 9600XT, Cooler Master CM 690/RP-600-PCAR
GA-K8NS Ultra-939, Opteron 175, 1GB PNY Verto PC3500, 9600XT, CM Centurion 5/RS-450-ACLY
A7N8X-E Deluxe, XP-M 2600+ @218x11, 1GB KVR PC3200, 9550, Lian Li midtower/RS-450-ACLY
AN7, XP-M 2800+ @218x11, 1GB HyperX, AIW 9600XT, Antec Super LB/TPII Blue 480http://classicplatforms.com
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