Hi,
I am not sure how helpful this will be, but here goes.
The cheapest method I have used in the past is a mobile phone camera set to video, and holding it very still.
The only other way I can think of, would be to install your screen recorder onto another computer and attach a KVM over IP device to the PC you have issues with, access the KVM over IP on the other computer and boot your faulty PC (so your video output will be shown on your other computer in a java window, the one with the screen recorder) and record that. The big down side of this method is the cheapest KVM over IP devices are about £200.
As I said not sure how helpful, but it's an idea.
Kind Regards,
Tim