1. Should I spend $400 on my current (3 year-old) build:
(I've included the lowest ebay completed listings for used sales as of today June 12th, 2012)
Intel core 2 duo E8600 Wolfdale 3.33 GHz $104
Gigabyte EP45t-DS3R $148 (buy it now, couldn't find completed listings)
Nvidia Geforce GTX 260 896 mb $50
Corsair DDR3 1333mhz cm3x2g1333c9dhx 2x2gb $10
Western Digital 640gb HD Sata II 7200 RPM wd6400aaks $25
Maxtor 200gb HD 6y200m0 $25 (wow, really, same price as the 640gb...)
SAMSUNG 22X DVD Burner/Player SATA Model sh-s223q $20 (buy it now, no completed listings)
Cooler Master 750w PSU $45
Cooler Master Cosmos ATX Full Tower (RC-1000-KSN1-GP) $52
2. Or try to sell it for ~$400 and instead spend $800 on a new rig? ( http://pcpartpicker.com/p/9Yej )
(Notice that the linked build has a Mini-ITX case and a mobo with a Intel Z77 chipset; these are deal breakers if I were to build a new rig since I plan to get an i7 and surround sound headphones by X-mas. Also, I can do without an Optical Drive or buying a new OS to meet my budget.)
Basically, what will allow me to play Guild Wars 2, SC2, BF3, and CoD: Black Ops 2 at better settings: $400 of upgrades on my current system or a (Mini-ITX) ~$800 rig?
Please advice me on how to best spend $400 on upgrades, or how to optimize an $800 Mini-ITX build that will outperform an upgraded 3-year-old system for the games I mentioned.