I have been running an X570, 5900x, 64gig mem, 12 gig 4070, Main NVME 2 gig, gen 4 for years. I want to move up to AMD 5 but a very limited budget considering new mem, new CPU. What mb should I look for USED, and what CPU to go with? Is the price of even USED mem going to cripple my ability to upgrade to something that would make a significant difference to what I use now? Main use is daily routine and older AAA gaming titles.