Advice on my next upgrade

[SlowTwitch]

I built my first computer a little less than a year ago. As I'm sure many people on this forum have experienced, the temptation to upgrade is irresistible sometimes. Right now I have about $350 burning a hole in my pocket. Firstly though, here is my rig:


CASE: BitFenix Shinobi
CPU: Intel Core i7 3770k 8MB L3 cache (overclocked to 4.2 Ghz)
CPU COOLER: Corsair H100i
MOTHERBOARD: MSI Z77A-G45 (3 PCI-E x16 slots)
RAM: 16gb (2x8) Corsair Vengance DDR3- 1600 1.5V
STORAGE: 1TB Seagate Barracuda 7200 rpm with added 30gb ssd caching
GPU: PNY GeForce GTX 670 2gb
PSU: Corsair RM650 (650 Watts)

The main use for my pc is gaming, followed by general use. I use a 24" 1080p asus monitor with a 2ms response time. What are your suggestions for an upgrade? I have that
1. I should get a large ssd for storing games and such (prices vary)
Or
2. I should get another gtx 670 and run it in SLi (cost just about $350 new)
I'm leaning more towards the 670, but there are probably some really great alternatives to the two choices, so any input would be great! Thanks!

 

[ps3hacker12]

A second 670 would probably be your best shot, quick entries into a PSU calculator under full load, with te overclock, your system would be pulling:

from the wall, your PSU should be able to handle that, but you may also need a PSU upgrade if you find your system cutting out.