Help with PC upgrades on a moderate budget?

[episteme]

Experimental42 said:
Intel Core i5-3550 Ivy Bridge 3.3GHz (3.7GHz Turbo) LGA 1155 77W Quad-Core Desktop Processor Intel HD Graphics 2500 BX80637I53550

ASUS Maximus V Gene LGA 1155 Intel Z77 HDMI SATA 6Gb/s USB 3.0 Micro ATX Intel Motherboard

SAMSUNG Spinpoint F3 HD103SJ 1TB 7200 RPM 32MB Cache SATA 3.0Gb/s 3.5" Internal Hard Drive -Bare Drive - OEM

G.SKILL Sniper Series 8GB (2 x 4GB) 240-Pin DDR3 SDRAM DDR3 1866 (PC3 14900) Desktop Memory Model F3-14900CL9D-8GBSR

Those are some of the discount pieces put into it. It's working now but I don't think it's very powerful anymore. She told me not to get my hopes up when she fixed it. I can't find the receipt for the graphics card replacement, but it was a dirt cheap one on newegg apparently.

That's what you already have and you still have a $600 budget?

CPU is totally enough, RAM should be fine, too. I have 16GB, but mostly for x264 video encoding with insane settings (can take up to 6GB alone).

Just buy a $250-300 graphics card like a R9 280X (good value for money) and maybe a SSD like the Crucial MX100 (not needed, but overall better experience).