I think my laptop it's not supported but works OK!
 

Hi.
I´m working with Windows 7 Home Premium 64 bit in both a desktop PC and a laptop with Pro Tools M-Powered 8.0.4 and a Fast Track Ultra. I was having problems with noises and crackles that were even recorded in both PC's, but now, everything works OK after turning off the WiFi.
My desktop:
Custom built: Asus P6T, Core i7 920, 6 GB Ram (triple channel), Windows 7 Home Premium 64 bit, nVidia 9500 GT 512 Mb, some hard disks, etc. I use it for mixing because it's a really powerful system. I was always sure there wouldn't be any problems with this PC, but I'm surprised with my laptop, that runs Pro Tools M-Powered 8.0.4 with no problems and very, very stable.
My laptop:
Acer 4740-6873: Core i5 430M (2 x 2.26 GHz), 3 GB Ram, 320 GB hard disk, Intel GRaphics (integrated), Windows 7 Home Premium 64 bit.
I know it's not a recomended laptop but works REALLY GOOD. It doesn't have Firewire ports, so I'm using an external USB 2.0 Hitachi Hard Disk (7200 RPM) with excellent results.
I even decided to make some experiments so I used a SanDisk Cruzer Micro (NTFS formatted) with a 32 track session and one video track... and guess what? It played perfect... as soon as you don't zoom in the edit window. Just for testing purposes, don't do that in a real situation.
No problems at all with the Hitachi USB 2.0 hard disk.
This laptop is really unexpensive and it's powerful too. If I have to record some channels outside, no problem. Just remember turning off WiFi.
Of course, if I have to mix a heavy project I´ll use my desktop, but if I have to record, mix or edit something not too heavy on location, I know I can do it with my laptop.