My system: m2n-sli deluxe athlon 4400+ geforce evga 8600GT kingston 2048mb (2x 1gb) 667mhz hd 160gb samsung sata2 Hey guys, first, sorry for my english, hope you can understand I bought this PC two months ago, and it already came with those errors, but they do not happened often, so i didnt worried about. It already happened when i was navigating with IE, or playing a game, so its not with a specific program, but they were very rare. But just now i was playing Battlefield 2 online and it was crashing on and on in the midle of the game. It is the first game im playing online in this PC. If i remeber well, i got no crashes (memory errors) playing this game with bots, offline. I must have played this game OFFLINE like 4 or 5 hours total with none of these errors, while ONLINE i got like 5 errors in 40 minutes. The game crashes to desktop when the error occur, with the buttons OK and Cancel, both seems to do the same thing Now, i got a fe of those errors too playing NFS Carbon, never played it online tho, always offline, so i dont think its totally related with playing online With F.E.A.R. (and expansion) and GTA SA, i got absolutely no crashes at all during the game, i played both till the end, several hours, no errors at all The error is : ""The instruction at xxxxxxxx referenced memory at xxxxxxxx the memory could not be read" Sometimes it says "the memory could not be write" , and the numbers (where i wrote xxxxxxxx actually there are numbers and letters) varies, and sometimes its all zeros, like "The instruction at 00x000000 referenced memory at 00x000000 the memory could not be read". Also i ran memtest, the one you run under windows, that only tests the free memory, and the one that you run under DOS, with a memtest boot CD, both i let running all night. No errors. Anyone have any clue what this could possibly be ?? Sorry for the long text, i just tried explain the best possible cause i know this error is very difficult to solve since it appears to have several causes, so i wont be surprised if noone answers Thanks everyone