Random BSODs, freezes and artifacts Hello, I have random BSODs (mostly while gaming, but not exclusively), freezes (always while doing stuff on Windows desktop or while navigating the Internet. Everything gets stuck and I have to manually press the reset button) and artifacts (always at the bottom of the screen, on Windows desktop. It looks like shifted squares, hard to explain. I have to minimize and maximize a window to make it disappear). It has been like this for months now. Sometimes I can get up to five BSODs a day and sometimes I get none for four or five days in a row. I don't really remember when it started. I think I have artifacts since long ago, but only when I use the latest Nvidia driver, not with an old one. Now I will make a list of what I have already done to try to find the problem: I updated all drivers I could (BIOS firmware already up to date) I cleaned my computer including fans and slots (RAM, video card, etc) I checked for overheating I tested the RAM with Memtest86+ two entire nights I bought new different RAM sticks and tested them with Memtest86+ an entire night I manually set the RAM timing and voltage in the BIOS I tested one stick of RAM in each of the motherboard's slots, and then the same with the other stick I bought a new PSU and checked all voltages while the computer was idle and on heavy load I unplugged all USB devices except the mouse and the keyboard chkdsk /f /r I disabled the pagefile sfc /scannow I reinstalled Windows on another hard drive Here are my computer's specs: CPU: Intel Core 2 Quad Q8400 Motherboard: Asus P5QD Turbo RAM: Corsair (XMS2) DDR2 800 MHz/PC2-6400 (2 sticks of 2 GB each) GPU: NVIDIA GeForce GTS 250 (Asus) PSU: OCZ ModXStream Pro 600W OS: Windows 7 Ultimate 64 bit I changed the RAM (I now have the one specified in my computer's specs) because I found out something strange with my two old sticks: The computer does boot with one of the stick whatever the slot I put it in. The computer does not boot (well it kind of start, but the motherboard don't even beep, and it stay like that, with black screen) when I put the other stick in the slot 3 or 4 of my motherboard (but the computer start normally when that same stick is in slot 1 or 2). I'm not sure if this is normal. I do not overclock my computer. The windows event viewer does not show errors apart from those related with the BSODs ("The previous system shutdown at xx:xx:xx on xx/xx/xxxx was unexpected.). I have been keeping some of the minidumps files from the BSODs I got. I have been trying to get useful information from them with the Microsoft Debugging Tools but I really don't know what to understand from them, so here they are. I'm really desperate. Thanks in advance for your help. -Nineven- EDIT: Problem solved. Defective graphic card (video ram).