Barry. I found that the biggest gain when I revamped my desktop was putting in the 1TB hybrid hard drive. Changed the RAM cards, as ya do, mainly to ensure that they were not age related deteriorated, but whatever you do the Motherboard and processor, plus the power supply capacity is a permanent limiting factor. I also goy myself a touchscreen monitor and a backlit keyboard. Well worth it. I would change your hard drive. Get a cloning app sorted and you will lose nothing including settings .