Here's my thoughts, please fell free to contradict whatever I say!
1. The GPU will probably be bottlenecked by that processor but if you plan on upgrading your processor/motherboard in the relatively near future that shouldn't be an issue
2. What make/model/wattage is your power supply?
3. If you're gaming at 1080p or below most games will not benefit from the extra 2Gb of vRAM though badly optimised ones like Watchdogs may