Black screen after updating, like no signal is coming to monitor

[Stercus accidit]

I have just "finished" updating my Ubuntu 9.10. (somehow I knew that something is going to go wrong), and now my PC starts, works fine for a few seconds, then I get a black screen for a moment, and then my monitor starts acting like PC is off.

Interestingly I think that otherwise everything is working just fine and that I just can't see anything due to the black screen (monitor is flashing like there is no signal coming from PC). Any ideas?

[~!geek!~]

OMG not again. Dude try to search for:
black screen after upgrading to ubuntu 11.04 ubuntu forums
in google. There are a lots of threads created discussing the same problem again and again. Just follow one of those old threads.

[Stercus accidit]

Will try. Thanks!

[Stercus accidit]

Found this video http://www.youtube.com/watch?v=f8y29gqX9SU, fallowed the instructions and it worked for me. Just to mention that you have to press shift at start to be able to open grub. :D