Hello! I just made a custom-clean installation of Windows 7 Ultimate 64x upon Windows Vista Home Premium 32bit and I want to ask the NORMAL disk space usage that Windows 7 OS requires! Supposed to have a 500Gb Hard Disk! However, in My Computer shows 465Gb total and after installing some programmes and putting some music...I didn't pay attention at first place (unfortunately)...seems that Windows 7 occupies about 20-22 Gb of Hard Disk just to run... after a rough calculation of my datas' capacity! Is that normal or somewhere I lost some hard disk capacity? Thanx in advance!