You can be discriminatory or prejudiced in some sense towards certain models or brands, yes - you can loathe Macs for no reason, and refuse to buy Macs, and not talk to people who have Macs, etc. But you can't be racist because, well, computers aren't a race.
Better question: if you do the above discriminatory actions towards a race (s in the track/athletics event) of a certain type, are you being racist?