Some people have gotten a "gray screen of death" while using their 4xxx and 5xxx series of ATI Radeons, and from what has been gathered, it is most common on the cards from manufacturers that use the reference boards from ATI (XFX, Sapphire, Powercolor, MSI, Asus). I wanted to thank this website and forum for providing hints through various threads and providing tools such as RBE, WinFlash and the BIOS database that was able to let me permanently fix this situation on my own, as no "fix" has been forthcoming from either ATI or the manufacturer of my card (Sapphire). Now I want to share what I found by digging into the BIOS for my card (Sapphire Radeon HD 4670 1 GB - new hardware revision w/blue PCB instead of brown). Apparently there are what are called "PowerPlay" settings in the BIOS to facilitate power-saving modes for all of the newer Radeons (2xxx and above), and this my friends, is wherein the problem lies. According to the information displayed by RBE, my particular card was using low-power settings that dropped the power of the card down to a Windows-95/98 era PC when idle, and these settings were explicitly labled "For notebook computers running on battery power". I was like, ok...since when do you incorporate "notebook computer" power schemes into a standalone desktop/workstation video card? The answer is that you don't. Ever. The low-power settings and voltages were entirely too low for a desktop card, and it was causing all sorts of issues when swapping from 2D to 3D and back in Windows, especially when swapping from a 3D environment to a 2D loading screen in games. The cards are not getting enough power at the low-power settings it swapped to, and the card basically vomits when Windows attempts to recover the video driver - thus locking up and showing a gray screen with very thin orange or green vertical striping in quite a few cases, and gray/white/black striping in others (this seems to be card model dependent as well, with 4xxx series owners and 59xx owners showing the former, and 58xx series owners showing the latter). Now, what did I do to fix it you ask? It's simple. I changed the voltage and core/memory clock frequencies found in a BIOS I downloaded from TechPowerUp and flashed my video card with it. No more ridiculously low power-saving settings. I believe in my case, I was at 216 Mhz core, 115 Mhz memory @ .09v, and was like....wtf. I changed all of those settings, except the previously assigned "Boot" setting and the "Power" setting (the one that displays top overclock limits) to the default settings for my card, which in this case was 750Mhz core/800 Mhz memory @ 1.25v, and the fan settings I tweaked as well (in my case I put the fan to 100%, 100% of the time as I don't mind the noise). If I want to swap into low-power mode at any time, I will just use the power settings in my OS to go into sleep mode/hibernation which turns power to the card off - thanks anyhow ATI. I would really recommend at least (if it is available in the database), downloading a copy of your video card's BIOS, and checking the settings contained inside if you are having this problem. Several users on the AMD forums got relief for their cards as well with modified BIOS software from their card manufacturers (there's a 98-odd page thread over there about this issue). A partial fix involving Overdrive profiles was found for the 5970 cards, and was a good indication that I should dig into my BIOS, as well as people in this forum mentioning certain things in their problem threads. I hope this helps some people fix this on their own instead of having to RMA their cards or give up in frustration that their cards will ever work (aka, waiting on pokey AMD/ATI or their card manufacturer to quit screwing around and release a proper BIOS update). Of course, changing the settings and flashing the card is at your own risk, and may void your warranty - In my case, I didn't care about the 1-year warranty on a $70 video card, I just wanted it to work.