If you need a PC which is powerful as well as green and efficient, then Dell OptiPlex 755 with Intel Core 2 Duo with vPro technology has to be the answer. Used hugely by corporate sector as a business machine, this computer has delivered a lot in recent years. It is experienced by a large number of professionals and hence been tested on plenty of different avenues with great success. It's 500GB hard drive given you enough room for storage. 4GB Memory (expandable to 8GB) gives you good internet surfing experience and while downloading and loading various apps. It's integrated Intel graphics card produces crisp images even good enough for graphics related works. DVD writer is an additional added advantage. Full details of the product specification could be found at the link given in the last row of "Technical Details". Finally, the good news is that it's loaded with Windows 7 Professional with all the latest updates (and hence the service pack). It is provided to customers with Genuine Windows 7 Professional Installation DVD and a Certificate of Authenticity (COA). It's an absolute bargain.