Environmental problems arise from the rapidly developing personal computers and are gradually becoming a significant part of problems. Computer industry are usually viewed as relatively clean. However, discarded personal computer and related equipment which are piling up at warehouse, or going to landfills has on the negative effects of hazardous substance on health and the ecosystem are growing problems which did not trouble society a few years ago. This paper will estimate the quantity of the obsolete personal computer in 1999 and suggest the alternatives of its disposition.