Thank you for the rundown of things to check. I haven't really done troubleshooting like this before, so this is going to be interesting. I will look for the bank swap on the forums and hit up YT for some tutorial videos. Thx.
So, the test starts just fine, with the text intact. Then on the 1st look, as soon as it hits that 18th square, the text flips through characters in the video, then stops as soon as it moved to 19th square. It then completed the loops, all green. Then starts next loop, all OK until the 18th square, and same happens. And so on...
I ran the test for about 30 mins, and it never crashed.
The machine seems to work fine otherwise. I played some games, ran some demos and no issues I can tell. Never hangs, and this is the only time I've seen the text garbled in any application.
Alright, sounds like I have some testing ahead of me. Thank you for the pointers.