patrizio, this sounds like an underpowered
psu, The motherboard and videocard and memory are demanding more power than there is available. If you are using 2 sticks of memory you could remove 1 of them for testing purposes (less current draw), I've even underclocked(shudder) a
cpu to pinpoint this problem.
Bob
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EP-8RDA+ v1.0 3827 bios
XP1700+ JIUHB 175 x 12.5=2187MHz. 1.75v
2 x 512MB Crucial pc3200 10, 2, 2, 2.0
THERMALRIGHT SLK900u 92mm Zalman fan, Enlight 420 watt, AIW 9000 Pro 64mb DDR agp4x, voltage mod 1.85v
Home made NB cooler