I have like 30 Sanyo XU 78 projectors. I have a few different classrooms that occasionally I will get a complaint about the projector blinking and then not showing anything, no error messages just no video. I have seen it before and when I saw it the first thing I thought was I lost the signal somehow so I changed the Monitor settings on my PC to 70Hz and the screen came on and it worked OK. So this is my quickfix, how do I stop this from happening in the future like after reimaging PCs and such? There was previously HP projectors in all of these rooms and we never had this issue. Any ideas would be greatly appreciated.