Unfortunately he never got back to me. So I got the second best offer there, which was a sapphire 6950 for $100. Maybe if I make my money back I'll buy another one

I did that, my batch file for troubleshooting was just

cgminer -o insertpoolhere.com -u username.1 -p password -I 11

This was with default clocking on the cards. When I raised the intensity to 13 I started getting hardware errors for both cards.

So I've started mining for alt coins with a 5870 and a 6950 in my rig. I did a little test run without optimizing anything to see if they could handle the load (I just set the intensity at 17 for both of them and left them alone for a day or so). Seemed like they were fine. So afterwards I did a little overclocking (and I really mean a little, like 50-100 mhz overclock), I raised the intensity to 18 for the 5870 and 19 for the 6950 and left them alone. A few hours later I come back and I see that the 6950 has spit out some hardware errors (I think it was around 4), so I lowered the intensity and tried again. This time it spat out double digits instantly. So I removed my overclocks and set them back to 13 intensity for both. Now they're both spitting out hardware errors right when I start CG Miner. So I've been troubleshooting for the past few hours, looked through forums for solutions and I've removed CCC (I had the most recent one) and reinstalled 11.1 and 12.1. Didn't help, CG miner was still showing hardware errors. So I tried using an older version of CG miner and for some reason the hardware errors stopped. Is there a reason for this? I'm stumped as to what caused the hardware errors to continue. And on a sidenote, can these hardware errors actually harm my cards? If you managed to read all the way to the end, I applaud you and thank you.

Lets not turn this into a pissing contest. Yes I'm aware that I spent a massive amount of money on my 780. It was what I thought was a good card at the time. But for the purposes of mining, they are shit. Complete utter shit. If anyone knows of a better card that has a better KH/$ than what I'm trying to get, speak up.

I don't know if it counts as overclocking, but I was going to flash the cards and turn them into 6970's.

Yeah it's second hand, and I really wouldn't use it for gaming, I have a gtx 780 on my pc.

If I did buy them I'd use them to mine alt coins. Are they worth it though? I don't pay for electricity if that changes anything.

Pretty pathetic compared to most guys here. About 800 Mhash using a gtx 780, a gtx 570 and an hd 5870. I use it to mine alt coins though

UGHHHH as excited as I am to see this in Calgary, I am not excited about travelling in this weather. Glad to hear about you guys though! I will be visiting you when you open!

If you buy that or any rig today, you'll never ROI. The difficulty is too high and the hardware costs too much. You're better off just buying bitcoins or mining alt coins with GPU's.

Thanks for the advice everyone! Really appreciate you guys helping out a noob. The guy lowered the price to $75 but I think I'll just buy bitcoins as you guys said.

Hi everyone. I just got into mining recently and I have to say I find it quite enjoyable. Now I'm not looking to make loads and loads of money right away but I do want to take advantage of my situation. I have "free" electricity (I live in an apartment and all we pay for is rent), and some money to move around. Would it be better for me to invest in bitcoin or buy some mining gear to mine alt-coins (I was thinking about either a 5870 for $100 or an r9 280x for around $350)?