Start saving up now and then go for a purchase in late summer/early fall, that's a good time to buy a rig as new chipsets and products usually come into stock, driving down the price of existing ones and there's also always a preparation push to sell out excess stock before the demands of Q4 set in.
I usually buy parts in August/September, by that time you should have had ample time to save up for a decent rig. Contrary to popular belief; you don't need a 1000$ rig or a 2000$ beast to play games on PC, that's mostly for maxing the hell out of settings and the more heavy mods that require more oomph.







