Do you have Vitashell or any overclocking plugins installed? I run Vitawave at CPU 444Mhz GPU 222Mhz (which should be the default for Vitawave). Make sure any cover art used is about 600x600 and about 100kb or less in size and any background images used for custom themes is less than 200mb in size. Categorize all songs by album folders as well. I don't know which one helps the best but I used to have GPU crashes all the time and now I never do with Vitawave :)
