No experience with Bystar, did they ever say what failed under warrantee? I would want to know. Maybe they are using inferior components. Or maybe there is an issue with spikes/surges coming in through the AC mains or peripherals (poor system design or specific wiring fault with your system), if this is the case then chances are whatever you replace their PC with will fail too. At a minimum, use a high quality surge supressor or voltage stabilizer/supressor for the PC.
Are there proprietary peripheral expansion cards or backplane within Bystar's PC that makes it so expensive?
I am currently building up my own custom 5 axis CO2/Excimer laser CNC system for my company. I typically use Axiom industrial chassis, when fully populated the cost was around $1200 (2.4GHz P4 CPU, 512M Ram, 40G hard drive, CD burner, floppy, NIC, 32M graphics, 350W supply)
Hopefully someone else will reply who has experience with Bystars.
Good Luck!
Wheels within wheels / In a spiral array
A pattern so grand / And complex
Time after time / We lose sight of the way
Our causes can't see / Their effects.