Atomic Systems

no nothing else crashes it runs all the latest top spec games needing huge graphics and ram

the spec is windows xp media centre edition, 300gb hard drive 7200rpm sata, 1024 ddr ram, ati radeon X600 pro graphics card, intel pentium 4 processor ht 550 3.4 ghz 1mb cache, c-media 7.1 sound card, 16speed dual layer burner

I have a new pc with 256mb graphics card, 1024 ram etc etc and msts keeps crashing constantly, even microsoft are beat any ideas anybody, I am desperate now