My story. Scroll down for TL;DR version. Alright, I'm new to these forums, I joined out of desperation. Here's the problem, and I'm sure you've heard it before. After installing the newest ATI/AMD 10.12 display drivers my windows 7 64-bit machine won't boot properly. I can get into safe mode, but for some odd reason trying to uninstall the driver from there mucked up the install and made itself remove itself from the list. This in turn left many files behind, I then used driver sweeper (from here) to clean everything up, that worked as planned but upon logging into windows 7 under normal safe mode (not with networking or CMD) or just normal boot up causes a Blue screen of death, the error messages have varied as I changed things, from IRQL_NOT_LESS_OR_EQUAL to a recent one (after I uninstalled the HDMI audio from system>device manager and the video card driver) SYSTEM_SERVICE_FAULT (or something of that resemblence). Now the thing here is, sometimes I can get into windows and have it crash within 10 minutes. I don't understand why it could be so buggy, I tried downloading as many updates for windows I could. As I am writing this I just got another IRQL_NOT_LESS-ect Now before today I ran my machine on a 400W power supply with the following specs, Asus P5K SE/EPU Intel Core 2 Duo E7300 @ 2.66mhz 2 Corsair 2GB Ram Sticks @ 800mhz 2 Geil 1GB Ram Sticks @ 1066mhz 1 Sata HDD 1 IDE HDD Nvidia 9500GT GFX I then replaced the nvidia graphics card (after removing the drivers via the uninstall in programs & features) and replaced it with an ATI HD 7550. Now, I read the manual, it did say, use a 450W power supply but I thought, the least that could happen was it wouldn't run. It acctually ran fine, although it immediately bluescreened (I believe, I did not see it) after the inital reset after the install of the drivers. (10.12) I then ran just cause 2 in high quality and It ran beautifully, I then proceeded to test the card, see what it could do, I was excited (possibly my downfall?) then I went and played crysis: warhead, turned it up to gamer, fearing enthusiast might be a little too much for it. I then played the game for a good half hour, with a few stutters until the game locked up, and I'm not sure but it was just a stuttering sounds lockup so I reset my computer and left it for a few days. I then put the old 9500GT back in and booted into my ubuntu partition which still had my Nvidia drivers (I never booted into windows with my old card again). Today I went out and bought an Antec 902 Case and 750W Antec PSU. I connected all of these things up and ever since, I have had blue screens tormenting me. I have gone through all sorts of measures to attempt to un-install these drivers. I have noticed that LOWER resolutions used to keep the BSODs at bay, but right now nothing but blue screens here. tl;dr To cut a long story short, can anyone help me? I need to have my ATI 5770 working. I used 10.12 that gave me blue screens, I can only use safe mode. Let it stand that I have had NO trouble with my computer until now. p.s. sorry for the large block of text, I am going to swap my nvidia card in now to see if I can get into normal windows.