I recently placed a post in the Video Cards section, as I at first believed my problem to be related to my 4870, but now I know differently. I've looked for a delete button on my thread, and can't seem to find it. Apologies if this has caused a problem! I wasn't sure whether to amend the last one or start this one. I'll mark the other one as needing deletion. I've been suffering random crashes, which manifest themselves as a frozen screen in-game or on Youtube and sometimes just cursor loss. Tabbing back to my desktop shows a black screen with various menus and opening and closing and my toolbar is placed on the top of my screen. I cannot do anything at this point, including trying to ctrl, alt + del so I have to press the refresh button. Knowing the 4800 series to be buggy, I blamed it on my card, but today I suffered another crash but was fortunate enough to make out an error message: 'dwm.exe application error'. I've had a search and as far as I can see dwm is responsible for the Vista graphics. I've not been able to get any further than that as it seems to be a fairly rare problem, except I did come across a dodgy offer of a downloadable program that can fix my registry. I'm confused at this point. This is a new PC and I know it's come with a restore disk, but I don't know whether that can just repair a faulty registry? I've tried contacting the makers of my PC and their online messaging system appears to be down. Is there a registry repair tool out there that's trustworthy and would it work? To be honest, I'm scared I've been stuck with a rather expensive lemon and really not sure what to do. Any suggestions would be greatly appreciated!