вот нашел тебе ссылку
ht tp:// as k ubu ntu. co m/qu est ions/20 5021/ho w-to-so lve-gpu-lo ckup-swit ching-to-software-fbco n-on-n ew-inst all-of-12-1 0
Убрать пробелы разумеется
How to solve “GPU Lockup - switching to software fbcon” on new install of 12.10-desktop-amd64
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Error occurs during startup of Ubuntu Installation. Sometimes I'll get to the Welcome screen just like this, the screen will just glitch out, or will simply freeze during the loading icon.
nvidia GTS 250
Intel Core i7 920
9 GB Memory
I was able to install 12.04.1, but after performing upgrade to 12.10 it get the same problem on startup; glitches in graphics, missing content etc. Also noticed after the upgrade, I'm no longer able to connect to internet; neither ethernet or wifi.
Ответ
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Solution for me was
Boot using live disc. Hold down shift to get to boot options. You should get a menu to try Ubuntu before installing, Install to disc etc etc.
Hit F6 and choose nomodset, then press escape.
Choose the boot option you want.
If you get in then you will likely need install the proprietary driver for you card.
Hope this helps you.
и далее комментарий -
Small problem that I ran into: You have to press [space] to activate nomodeset