Thanks, serje, for your advice.  I'll admit that mining is still appealing. 

Because it sounds as if you're a miner, I pose the question that I asked before about compatibility.  How compatible are the different softwares with the different hardwares?

I recognize that you suggest that AMD produces better graphics cards than nVidia.  For this reason, if I choose to buy graphics cards for mining purposes, they'll certainly be AMD.  However, the cards that I already own are nVidia cards, and they're not top-of-the-line.  When I tried to use one of them with Eobot, it said that I needed an openCL driver, which nVidia doesn't provide for the cards that I have.  Will this be the general case with all mining software, or is Eobot so unpopular that it's out-of-the-norm?  Could I mine with the standard cards that I have, (though it wouldn't be very efficient) or are there only certain cards that will work with certain software?  Or is it that there is no software out there that will let me use a GeForce 6200 graphics card by nVidia?

My first guess is that most mining software would support the most popular GPU cards, like the AMD Radeon HD 7950.  Would I be right about that?

If I do choose to use GPUs, I don't want to run into compatibility issues with the software.  I'd hate to buy a bunch of graphics adapters just to find out that I can't use them because I can't find the right software to mine with them.  For this reason, I'm thinking about compatibility.  Is it just a matter of buying the most popular cards, like the AMD Radeon HD 7950, which will then work with nearly all of the software?

If mining is becoming less popular, then I have a harder time buying new top-of-the-line hardware that will be obsolete in a year, rather than simply using hardware that I already have, or older stuff that costs next-to-nothing to buy.  But compatibility is important because if I can't find software that will work with what I have, then all of the hardware is worthless for this purpose, and it may make sense to abandon the whole idea.

Thanks again, for any input that anyone is willing to provide.

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