honestly though how many quality parts can you get for $300? a good power supply and a mediocre graphics card will will destroy that budget and force you to have to cheap out on the processor and mobo. that's a short term build at $300 and that's maybe buying used parts that you can't even vouch for who did what to them.
my last build from 2009 was probably like $650 and i cut corners on everything but the processor, mobo, and graphics card which were the Q9550, P35 Neo FR2, and 5770.
btw that Q9550 is going for like $125+ on eBay right now
Intel Core 2 Quad Q9550 2 83 GHz Quad Core BX80569Q9550 Processor 0735858197380 | eBay
i'm probably gonna list mines on there and if it sells for that it will be approaching me getting back almost half what i paid for it approaching 3.2 years after buying it. i just sold that 5770 for $55 also approaching half of what i paid for it.
if you spend the money for the better system up front you can dump the parts in a few years and roll that over into your next system and have had a better system for it rather than spend $300 on components that will be dated very quickly.
if you bit the bullet back in its day (2006/7) and bought an 8800 gts you're just now almost hitting about the minimum requirements to run a game like Max Payne 3. that's 5-6 years off that card for what was probably $300 or so back then and at that time you'd have enjoyed being in the upper echelon of performance for a time.
