This fix has been around in Ubuntu world for a while, and though it never worked for me before on my laptop when running Ubuntu it (so far -- only running for 10 mins since) seems to have done the trick on my new Wheezy:
#add the following line in /etc/modprobe.d/local.conf: options drm_kms_helper poll=N AFAIK the bug may be specific to the Dell Lattitude E5420 or rather some piece of hardware in it, if you can find out what this is then this line could be added at install to avoid the problem on those systems. If I don't send any more mails re this bug then please assume the fix is still working. -- Dr Charles Fox www.5m.org.uk Researcher, Department of Computer Science University of Sheffield, UK