PC acting up more often now

I hope this is the final PC incident of the day. As expected it has been acting up more often. Earlier today, it had restarted itself after messing the display with lines thrice.

I have started shopping for a replacement. Should I stick with Acer? Has Dell gotten back its mojo. My last Dell was a lemon. Is Asus any good? I was disappointed with theirs and Lenovo's SG site. They were still touting Windows Vista!

Wonder when Windows 8 would be released.