upgrade to 9.1 on hp zv5000 no screen

Hi- I tried to upgrade from 9.0 to 9.1 on my NP zv5000 AMD64 upgrade went well until booting installed system. Then screen was blank for about 10min. No problem as a clean install is not a bad idea but I get same resull. I suspect the 1600x1050 lcd screen is the issue. Any suggestions b4 I try another clean install? Thanx Robert (Bob) L. Sandefur PE Senior Geostatistician / Reserve Analyst CAM 200 Union Suite G-13 Lakewood, Co 80228 rsandefur@cam-llc.com 303 472-3240 (cell) <-best choice 303 716-1617 ext 14