Thsi one is really strange! Occurs on two different computers, one is an\nHP laptop running Vista ultimate, and the other a desktop with win7 32 prof.\nBoth systems have multicore processors, one Intel (two core), the other\nAMD 965(four core).\nThe Phenom II desktop has dual ATI HD5770 video cards in crossfire. The\nlaptop HP9650, has a single fairly decent but not great Nvidia GPU.\n\nAnyway both will occasionally have a very short display "blink". Under\n"normal" conditions, other than wondering why, there seem to be no other\nindications or symptoms.\n\n"Old" Solitare was transferred to both machines from XP.\nOther that the problem I'm about to describe, no other difficulties seem\nto exist.\n\nIf the "blip" occurs while dragging & dropping a card the card may be\nduplicated! One is on the original card pile, and the other on the new\nlocation/pile. An undo will restore to just one card in the orginal\nlocation! Or, you can continue to play with two identical cards!\n\nBoth systems do have AVG active. Anybody else noticed this sort of behavior?\n???