CAN I USE KEY FOR MORE THAN 1 COMPUTER?

K my problem is that im gonna rebuild my desktop, its getting a new mobo, cpu, gpu, psu, and ram so a whole new build minus a hard drive, but when i swap these parts out, im kinda inclined to back up my important files, and do a disk wipe, and reinstall windows. so technically it will be a different computer. my question is if i buy pyxel and download it now, may i reinstall and use it on my pc after i rebuild it?