Problem: loud computer fans mess up home recording studio vocals

I don’t want to build an isolation booth for the vocals. I live in a wonderfully quiet place and have no problem in the winter but now that it is warming up, my computer fans come on and mess up my recordings. The AC is too loud and takes too long to cool the room. Throwing a thick blanket over the computer works great… until it gets too hot. So, today I decided to build a waterproof sound stopping ice blanket. First stop: REI.