Ok, so I have been half-@ss mining with my Geforce GTX 580, getting 120 MH/s and I am looking for an upgrade. My overall goal is to make at least enough to pay for rent, which is $600 a month. Using the mining calculator, I figure I need to be running at least 620 MH/s (not taking difficulty and exchange rate changes into consideration
Now, I'm looking at investing in a new graphics card, but here's my situation.
I have a computer just sitting here with i5 CPU and about 6 gigs of ram, and on-board graphics card (which is crap), and I have my main computer with the GTX 580.
Now, I know that difficulty increases has made mining less profitable, but would it be worth it to go nuts and spend $450 on a Radeon 5870 and put it in the old computer? or just get 2 5830's for $100 each and put one in each computer?
I plan on joining a pool, so it's not like I'm trying to solo here on 600 MH/s