PC is shutdown everytime when I use emerge --sinc command. System crash at updating some db cache system. When progress is 100%. PC is working few seconds then is turn off. IT's not like halt then system send kill message. PC is just turn off. Reproducible: Always Steps to Reproduce: 1. emerge --sinc mod_php 2. 3. Actual Results: PC is turn off Expected Results: No turn off, of course Sorry, I don't know how to paste all text from emerge list here..
This is usually either overheating or bad memory/cpu/motherboard.
heat/power/memory issues here, try running memtest on a livecd, using a larger power supply, or adding fans to help you diagnose your problem.