no, as long as the capiciters are good/*i have a few horror stories and dead x86 boxen to prove there a bitch*/ keeping the machine up forever is actually better then shutting it down. getting a 7200 rpm harddisk up to 7200 rpm takes a bit of work and where, things in motion tend to stay in motion. however, don't run shitty motherboards/computers constantly using seti iv killed three machines this way/*well, i was trying to kill one of them:;*/. however, if you have a decent mobo/processor keep it up and run seti for me. you also don't have to wait for it to boot up, its always there. i also run a lot of seti and run servers on all my boxen, by the way, does anyone want to start a windows-sucks seti team