Can anyone one of ya'll build a "reasonably" priced machine to mine with (PCPartpicker)? (college student ;D)
Not saying I'll buy it just curious what one looks like.
*Mobo with as many PCI-E X16 sized slots as possible (do not all need to be electrically X16), X1 is handy too for use with risers
*CPU and 2-4GB of RAM to be compatible with mobo
*As many Radeon 7870's, 280/X's, 290X's as you care to purchase and will fit in the mobo. (See note below on GPU's) 4 or 5 seems to be a practical limit in Windows based systems. Obviously spacing issues happen with the dual-slot sized cards, so you have to use risers (extension cables, basically) to connect the PCI-E slots to the cards.
*Nice power supply to power it all. Figure 150W for all other components + 300W per GPU. (Could be more or less, just round figures) If you have more than 2 or 3 GPU's in a system, you probably will need to have 2 power supplies.
*Any sized HDD/SSD. Some people have been going super cheap with like 32GB SSD's to run mining Linux mining.
GPU note: 7870's, 280 and 290 series are the only ones taken really seriously by miners for dedicated rigs... maybe 270 as well, since 280 and 290 have gotten so expensive. But you can start mining with any 6-series or higher AMD GPU.... (actually 5-series work as well) I started with a 7790 (same GPU as 260X) and it actually gets great hashes for the dollar. I paid like $90 for it, and it performs like roughly 40% of a 280X. (Which makes sense, since it has 896 shaders to 2048 on the 280X.) And of course a card like a 7790, 260X, 265, 270X will work in practically any PC (lower power requirements) with a fairly low dollar investment.
Oh, and NVIDIA cards are catching on. People are making improvements to cudaminer, and IMHO more improvements are likely. I do not think there is an inherent advantage to AMD cards; they just happened to be easier to program for mining purposes, so that was the first thing that developers came out with. Now that the AMD cards are so expensive/rare in retail channels, developers are turning towards NVIDIA and I think we will see some real improvements/tuning of the mining software. So any high-end NVIDIA card would work; and the new 250 Ti is extremely power efficient, so it may be a good place to start, especially considering that is it relatively cheap. Of course, this is more speculative than the AMD cards, so probably not the best place to start.
Basically, if you have all component parts of a desktop computer already, you can get into mining by just purchasing a GPU or two. If you start from scratch by spending money for a new dedicated mining motherboard, CPU, etc. then it makes sense to maximize that investment by using as many GPU's as it will handle.
You could seriously take an old, <$200 (today's used market price) Core 2 Duo system and put a 280X in it for a pretty solid little miner. (That's all that I have.)