I have a very strange problem: Since I have my new PC, I have always had problems with it. From time to time the computer freezes for some seconds and suddendly reboots by itself. I've had this problem since Ubuntu 9.10. The same with 10.04 and 10.10. That's why I don't think it's a software failure because the problem persist too long. It doesn't have anything to do with what I'm doing at this time. Sometimes I listen to music, sometimes I only use Firefox, sometimes I'm running 2 or 3 VMs, sometimes I watch DVD. So it's not isolatable. I could freeze once a day or once a week. I put the PC to the vendor twice(!). The first time they changed my power supply but the problem persisted. The second time they told me that they made some heavy performance tests 50 hours long but they didn't find anything. (How can that be that I have daily freezes with normal usage). The vendor didn't check the hard discs because they used their own disc with Windows. (So they never checked the Linux installation).
Yesterday I made some intensive hard disc scans with "SMART" but no errors were found. I ran memtest for 3 times but no errors found. I already had this problem in my old flat, so I doubt that I has something to do with current fluctuation. I already tried another electrical socket and changed to connector strip but the problem persists. At the moment I removed 2 of the RAMs (2x 2GB). In all I have 6GB, 2x2GB and 2x1GB. Could this difference maybe be a problem? Here is a list of my components. I hope that anybody find something I didn't think about yet.
And here a list of my components:
1x AMD Phenom II X4 965 Black Edition, 3,4Ghz, Quad Core, S-AM3, Boxed
2x DDR3-RAM 2048MB, PC3-1333 Mhz, CL9, Kingston ValueRAM
2x DDR3-RAM 1024MB, PC3-1333 Mhz, CL9, Kingston ValueRAM
2x SATA II Seagate Barracuda 7200.12, 1TB 32MB Cache => RAID 1
1x DVD ROM SATA LG DH16NSR, 16x/52x
1x DVD-+R/-+RW SATA LG GH-22NS50
1x Cardreader 18in1
1x PCI-E 2.0 GeForce GTS 250, Retail, 1024MB
1x Power Supply ATX 400 Watt, CHIEFTEC APS-400S, 80 Plus
1x Network card PCI Intel PRO/1000GT 10/100/1000 MBit
1x Mainboard Socket-AM3 ASUS M4A79XTD EVO, ATX
description: Desktop Computer product: System Product Name vendor: System manufacturer version: System Version serial: System Serial Number width: 64 bits capabilities: smbios-2.5 dmi-2.5 vsyscall64 vsyscall32 configuration: boot=normal chassis=desktop uuid=80E4001E-8C00-002C-AA59-E0CB4EBAC29A *-core description: Motherboard product: M4A79XTD EVO vendor: ASUSTeK Computer INC. physical id: 0 version: Rev X.0X serial: MT709CK11101196 slot: To Be Filled By O.E.M. *-firmware description: BIOS vendor: American Megatrends Inc. physical id: 0 version: 0704 (11/25/2009) size: 64KiB capacity: 960KiB capabilities: isa pci pnp apm upgrade shadowing escd cdboot bootselect socketedrom edd int13floppy1200 int13floppy720 int13floppy2880 int5printscreen int9keyboard int14serial int17printer int10video acpi usb ls120boot zipboot biosbootspecification *-cpu description: CPU product: AMD Phenom(tm) II X4 965 Processor vendor: Advanced Micro Devices [AMD] physical id: 4 bus info: cpu@0 version: AMD Phenom(tm) II X4 965 Processor serial: To Be Filled By O.E.M. slot: AM3 size: 800MHz capacity: 3400MHz width: 64 bits clock: 200MHz capabilities: fpu fpu_exception wp vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush mmx fxsr sse sse2 ht syscall nx mmxext fxsr_opt pdpe1gb rdtscp x86-64 3dnowext 3dnow constant_tsc rep_good nonstop_tsc extd_apicid pni monitor cx16 popcnt lahf_lm cmp_legacy svm extapic cr8_legacy abm sse4a misalignsse