Graphics Error with MC 1.5_02?

Hi, I'm sure I'm prolly in the wrong website/forum period, but I wanted to ask the Bukkit community seeing as people who use Bukkit have a fair amount of knowledge of more things technical.

For the past, we'll say "year" I've been playing MineCraft Alpha/Beta off and on, and when I would play it would be up to 6 or more hours a day (if I played even). I would see no problems what so ever from my computer, graphics were fine, and everything.

Now recently (as of MC 1.5) after a long time of play (say 5+ hours) my graphics will bug out. In 3ds max, this is called a "mesh explosion" when all the vertices just go completely out of whack, and pretty much obliterate the CGI build. On top of it, mesh doesn't keep it's texture, defaulting back to the magenta/neon yellow debug textures (that some use within their own engines).

What I'm trying to figure out if anyone else has really experienced this problem as well as I have, or if it's time for me to go buy some new hardware and do a lil repair work on my PC.

Edit: I wanted to add that 5+ hours and a reboot isn't a big issue to me, but if my gfx card is going out, I wanna get a new one before this one goes completely out.

 

In video settings, there is andvanced opengl, turn it on.

 

Yeah I've fiddle with both options, it still happens for me. I wouldn't come here and make a post if I hadn't tried all my options (not being a smart ass just saying; I dont' wanna get flamed on a forum I wanna be part of; so I try to do a lil research before I do post)