my current computer build:
http://pcpartpicker.com/p/nNpv23

Everything on this computer is around 4 or 5 years old aside from the power supply
Recently it has been running pretty slow, having issues alt tabbing from games to desktop / second monitor.
I am not sure if I should sink some money into it on things like new ram and whatnot or just build a new computer that can be upgraded down the road?

Pertinent information:
Budget: $700
More specific use (what games, what programs): Starcraft 2, Diablo 3, Counter Strike: Source / Global Offensive. Would play newer games if my pc ran them smoothly
Planned time until purchase: Not sure, more looking for some advise. Would probably been in 3-4 weeks
Do you need an Operating System?: On a new build I would
Do you have any specific preferred components?: Personally I would like to go with Intel
Do you need a sound or wireless card?: No
Do you want stock cooling or do you plan on overclocking?: Stock, nothing crazy
Do you need a monitor? mouse? keyboard?: No, have a few spare / can take from old build
Zip code/location? (Shipping costs): Ontario, Canada. I can ship in the US to 55605 and bring across the border if it is significantly cheaper (just have to pay duty when coming back to Canada)

Thank you for taking the time to read this; any feedback would be much appreciated

Have you tried getting rid of any bloat software or reformatting? Shouldn't have problems playing any game currently out at reasonable settings. An overclock on your processor would also boost performance quite a bit.

A lot of your components are salvageable, if you decided to build a new rig, in which, you'd be able to get something quite nice.

Ya id say just oc the cpu and buy a new gpu.
A 970 would be a wise choice, although a R9 290 @ 250$ is very appealing to me.
Buy more ram if needed, but really you could save cost there if you don't multitask a lot, I never used over 4gb when playing a game like Watch Dogs and having internet and a few programs open.

Wow. expensive i say upgrade uyr rich

http://pcpartpicker.com/p/6tTf23

meh