mouais mais regarde si je fais cette config:
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System Type: 1 physical CPU
Motherboard: High End - Desktop
CPU: Intel Core i7-870 2930 MHz Lynnfield
CPU Utilization (TDP): 90% TDP
RAM: 3 Sticks DDR3 SDRAM
Video Card: ATI Radeon HD 5850
Video Type: Single Card
Regular SATA: 2 HDDs
DVD-RW/DVD+RW Drive: 1 Drive
PCI-e x1 Card: 2 Cards
Fan Controller: Yes
Fans
Regular: 3 Fans 120mm;
Keyboard and mouse: Yes
System Load: 90 %
Recommended Wattage: 398 Watts
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348 W minimum d'apres http://extreme.outervisiosion.com/psucalculatorlite.jsp