System specs: - Intel P3 (Copper-933MHz, w/ stock alum. heat sink) - ASUS TUSL2-C motherboard, w/ BIOS v. 1011 - WIN 98SE (all standard updates) - Additional side case fan - Crucial 256 MB RAM (CL-2, 133MHz) - 250W ATX power supply - Soundblaster Live 5.1DE - GeForce 2 64MB video - Intel Pro 100+ NIC (no dial-up MODEM) Problem: this new system randomly shuts itself down (with no beeps)...it does this prior to, during, and after Windows 98SE loading, i.e., anytime from 2 seconds (before memory test) to 2 days after power button activation. After all random shutdowns, the green power LED slowly blinks...I don't know what this indicates...do you? Trouble shooting to date: swapped out motherboard, NIC, checked for interrupt problems (no conflict), updated all power mgmt drivers...these actions haven't helped...any other ideas? Thanks, TJ

I’d be suspicious of a PSU issue. If you can, try a bigger one. Also consider thermal instability. I’ve also seen this with an intermittent MOBO/case short circuit.

Try get a 300 Watt PSU should works on P3 and P4 system.

May be the juice at your location. Check your wall socket for voltage and shorts. Home power can fluctuate greatly at different times of day or when refrig compressor kicks off or when someone uses a microwave -- enough to shut down your PC.

Probably the WININIT trojan. Go into search and type wininit.* and remove. If you can't boot up at all then hit F8 and go to Command Line and path c:\Windows and type erase wininit.*. then restart.