If you have specific parts you are after, one of our experienced sales team will be happy to build a system that suits your needs. The parts are subject to change depending on stock availability but the specifications listed in the title will always be correct. If you do have a specific requirement, then one of our experienced sales team will be happy to build a system that suits your needs. Upgrade an existing graphics card or add a SSD with Windows installed if the PC only has a single hard drive (as the OS is already pre-installed). We cannot change components that are part of an existing build e.g. We can add any part to a PC for a small fee as long as we don't need to remove an existing part for it to fit, for example adding more RAM, an extra hard drive, or adding a graphics card to a PC without one (we can even SLI/Crossfire for you if it is compatible). Can I swap out parts and/or change/remove Operating systems in a PB Tech PC?