Setting up a new stream

i am setting up a live stream.

I use OBS to broadcast to twitch but i am dropping hundreds of frames, my PC has 8GB of ram and a really old graphics card.
i will soon be upgrading to the EVGA geforce gtx 970.
will this solve my problem? if not what will?

This is for developers. Please go here

Thank you, also would getting an external capture card help?