booting psx backup on www.modchipstore.com modchip (unsure of actual modchip)
 

Well at modchipstore.com it says that i dont need a gameshark for psx backups ... I know the backup works because I have tested it out onmy friends ps2 with a external sbox modchip but when i put it in my ps2 it just comes up with the "please insert a playstation or playstation 2 formatted cd" screen. I can't figure out what to do. Can someone please help me

You need to boot with the gameshark or action replay for copied ps2 games. go to start, w/o codes, then turn on usb mod and swap disks