Protools free crashes, please help.

[SysOp]

I've installed PT free in the following machine:
- Pentium III 450
- 192 MB RAM
- Mother Intel SE440BX-2
- Phoenix Bios 4.0 Release 6.0 1996-1999
- HD Maxtor 9153103 (15GB/ 3 partitions/DMA activated/ATA 66)
- Ram bus 100 mhz
- Sound card Yamaha DS-XG on-board
- Graphic card PCI

I can install the program but when I run it, it crashes at the very beginning, before the Protools sign appear so I can't precisely ensure at which stage of the loading process this happens. I've downloaded all the specifications and recomendations for PC and all seems to be right with my computer.
How can I solve this problem?