Intel Pentium IV 2.4GHz, 1GB RAM, 80GB hard drive, CDRW. The tower is very small, ideal if you need to put a computer into a confined space .This computer comes with a clean install of Windows XP Professional SP3 plus MS Security Essentials. No time consuming software to install and update, it is ready to plug in and use. I devote of lot of time, care and attention when manually rebuilding these computers, so offers below the asking price are not appreciated. I also do PC repairs, upgrades and pay cash for broken screen laptops if they are recent models.