A bit of a cryptic title, I admit! I am troubleshooting spontaneous shutdowns of a client's desktop PC that occur predominantly early in the boot-up sequence of a Vista-equipped PC when starting from cold.
The computer shuts down mostly during the first 5 progress bar animations of the Vista boot-up screen, but it can happen later in the boot-up process, up to and including the welcome screen. In almost all cases, though, this is only when starting the computer from cold (after it has been off for about 3 hours or more).
Basic hardware specs are:
- eMachines E4252 desktop (out of warranty).
- Motherboard: Abit NF-M2S / Acer EM61PM/EM61SM / ECS GeForce6100SM-M(2) / Packard Bell MCP61SM-AM.
- CPU: DualCore AMD Athlon 64 X2, 2100 MHz (10.5 x 200) 4000+
- Video: NVIDIA GeForce 6100 nForce 405 (128 MB).
- RAM: 2GB DDR2-800.
- Vista Home Premium SP2.
I have tried, all without success:
- Monitoring CPU temps: both cores run 35 - 45C (acc. to AIDA64).
- Replacing 300W PSU with new, 380W PSU.
- Testing with minimum peripherals (monitor, keyboard, mouse).
- Replacing RAM module, testing with MemTest86+.
- Disconnecting internal peripherals in turn: media card reader, DVD drive.
- Full HDD diagnostics (HDD, surface read tests, manufacturer diagnostics).
- Testing with PCIx video card (in place of the integrated nVidia).
- Updating Vista drivers for video card, LAN and WiFi NICs, etc.
- Different BIOS settings, particularly power=related (such as turning off AMD K8 Cool&Quiet Control).
I currently suspect a power-related issue with the mobo (faulty capacitor?), but I have admittedly not yet tried re-applying thermal paste to the CPU (since operating tempos are fine, and issue occurs on cold starts). Is there anything else you can suggest before I notify the client that the mobo needs replacing or otherwise advise investing in new hardware?