Brand new pc crashes and reboots with NO error message

.

mobo: Intel Product D946GZIS Field Version AAD66165-301
cpu: Intel Core 2 Duo E6300 Conroe 1.86GHz 2M sharing L2 Cache LGA 775 Processor
DIMM1: 512 MB DDR2-667 DDR2 SDRAM
bios: updated to the newest
Video Adapter Intel(R) 946GZ Express Chipset Family (128 MB) (onboard)
Audio Adapter Intel 82801GB ICH7 - High Definition Audio Controller [A-1] (onboard)
Disk Drive Maxtor 6V200E0 (189 GB, IDE)
Optical Drive LITE-ON DVDRW SOHW-1653S
Operating System Microsoft Windows XP Professional + service pack 2
Network Adapter 2Wire PC Port (172.16.1.34)

No heating problems, microsoft memory check shows no RAM problems. The system crashed even before installing 2wire network and now also gets disconnected from the net very often. (4 other older computers working on the same network have no problems)

The technicians in the company lab first told me the windows installation was faulty so I installed windows again with service pack 2 and all the new updates and it still goes haywire periodically. I spoke to microsoft - they said that it's probably a hardware issue.

Help!!! Please

p.s. I have no idea what the minidumps are

Both dumps list VisorUsb.sys as the probable cause. See if there's as update available for this file.

Thanks but it happened also before the visor was connected

I'll remove the visor all together....as it works on another pc fine....and if it crashes again I'll send the new dumps.

It has crashed again - see new dump

I uninstalled the visor, rebooted and 2 hours later it crashed again .
Please look at the new dump for me.
Thanks
Gila

Test the RAM with Memtest86+. If you get any more dumps, wait until you get at least 3 before posting them.

Sent the pc back to the vendor's lab as it has a 3 year guarantee. Will give you report of what they repair.

The pc came back from the lab. they changed memory stick.....I am hoping for the best.....will study how to read minidumps. thanks.