Laptop power supply issue?

[mrufino1]

have a strange question I think. I use an emachines 6805 with protools m-powered, firewire 1814, behringer ada8000, mackie 1604vlz in a 10/10 mixer rack to do mobile recording. Last Sunday I had a session at a band's rehearsal space and my computer shut down 3 times and twice reverted to 600x800 with an error message saying the graphics driver failed. I plug my computer and firewire drive into the power strip in the rack, computer ground is lifted because otherwise there is noise, then the rack is plugge dinto a UPS with a voltage leveler circuit. I just finished my pm-1000 preamps and put them in the rack as well, and I had messed something up while putting htem together so I took them to an electronics tech who got it working correctly. However, this was the first time it was mounted in the rack. Today at church I was recording as well, and during rehearsal it again shut down. I thought maybe it was the pm-1000, so I stopped using it, unplugged it, and no more shutdowns during the church service and mixing. SO, what might be causing this? Is the pm-1000 causing a voltage drop, therefore makign the laptop get screwy? I fugure the power supply is not very robust or tolerant. If this is the case, do you know of any higher quality laptop power supplies, or is there a way to adapt a desktop power supply to use with a laptop (or is there alreayd one commercially available?)? One of the musicians I work with was an electrician and is now a computer programmer, and he said this may be the case. He also suggested we build a rackmount computer using a server he has that is unused, which may be an option, but financially I'd love to not go all out on a new machine unless I really have to (in which case the laptop would sold to finiance the new machine). Anyway, if anyone has any ideas that would be great. Thanks-Mark