Hello Stephane_D,
Do you remember which was the BIOS version installed before you updated it to the latest one (0052)? We can try doing a BIOS recovery installing the previous version.
These are some recommendations for this issue:
- Test the system out of the chassis, minimal configuration please. (Motherboard, processor, power supply, and video card) No memory.
- Remove the CMOS battery and leave the system without it for about an hour. Then put it back on and restart the system.http://www.intel.com/support/motherboards/desktop/sb/CS-028780.htm?wapkw=clear+cmos+battery#datetime
- Turn on the system without the CMOS battery and then shut it down.
- Include 1 memory stick on the blue dim closest to the processor.
If all this troubleshooting does not resolved the problem, I recommend you get in touch with our Warranty Department so they can help you to replace the unit: http://www.intel.com/p/en_US/support/contactsupport
Regards.