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I think I did pretty well on it.  My goal was lowish power at wall / low initial investment.   I bought lots of parts used, or discount/rebate.  Let me know what you guys think.


Parts/prices include shipping.
$40 CPU/Motherboard/Ram: ECS 945GCD-M(1.0) Intel Atom 330

• Seller also included 2 GB DDR2
• Has 1x PciE 16x slot, 1 PciE Slot
• Pulls 30 watts at wall idle, no video card

$40 GPU1: 5770, XFX 577A-ZNFC
*Purchased used from a friend who was getting rid of his crossfire setup

$40 GPU2: 5770, XFX 577X-ZNFC
*Purchased used from a friend who was getting rid of his crossfire setup

$13.99 PSU: Corsair CX 430
*Bought ~6 months ago from newegg after rebate. I had a few extra molex to PCIE adaptors for the second card.

$8.98 Pair of 16x to 1x PCIE converters from Amazon, only ended up needing one of them.

Free Case, old beige box mATX compatible, cut a few holes in it to add fans.

$6 OS: Linux running on a 8 GB Flash Drive



Total: Cost $150.97
MHash: ~380

I'm running the pair of 5770s at 900MHz @ 1.125v.  Full load power draw is ~190w at wall.  I hoping tweak it farther to bring the MHash up to 400ish at similar power draw.  

Cost at current speed works out to: 2.53 MHash per $1 purchase price.  Running cost is right at 2 watts per MHash.

Think I did alright?

Edit, labelled pricing wrong.

Think you came a little late...

great very cheap

Yeah, I did start a little late, no big deal though.  At current difficulty rates and my power rate (0.08) I'm still making about $1 a day on it, so it should pay itself off in 7-8ish months. Even if I only make half of the money back, I still have the hardware I could sell off.  Plus it's fun just messing around with it.

and if its at all cold where your at, its auxillary heating!

For your first rig, you did fantastic!  Good work buddy....very cost effective on both initial investment and ongoing costs. 

When you get addicted and start pursuing ever higher hash-rates, that is when the real fun begins!

Wow, great job!

You don't mention what your marginal rate for electricity is.

 - http://tpbitcalc.appspot.com

If you are at $0.15 per kWh, then that rig will break even (profits accumulated will match the amount invested in the hardware) in one year.

That's assuming the exchange rate vs. difficulty doesn't drop further:
 - http://blockchain.info/charts/miners-operating-profit-margin

Imagine the break-even had you paid list price for everything though. :o

$151 for 380Mhash is pretty fantastic! Lot less than I've paid for my hashes :)

haha no doubt! Good job OP, I started about a year ago and before I knew it I was running four separate electrical circuits into my office!

Actually, it is 2 MHash/watt isn't it?

That really is quite well done OP.  My first rig was also my gaming machine so I had 450Mh/s at 310W for a whopping 1.45Mh/W.........not too good eh?   ;D

Ah, should have listed my price for power, $0.08 per kWh.  Used that calculator, works out to "Break even after   202.2   days", so my guess was about right. I live in the NE, so I don't have to worry about cooling with AC.  A fan in the window with a  cross-breeze is all I need to keep it reasonably cool. In the winter the heat generated will just reduce my heating bill.

Oh, my rule with list price, never pay it, ha!  I did get the video cards cheap, but it worked out well for both of us, they only sell for ~$65 used online, then you have to deal with shipping, paypal/ebay fees, etc.  $80 in cash works out a little less, but with none of the hassle, so we both made out :P



Still, not bad considering it was a gaming rig and not a specific mining rig.



Thanks!

GPU   Status   Temp   Load   Rate   Accept/Invalid   GPU Family   Fan% (rpm)   Core   Memory   Power
0   us1.eclipsemc.com
   63.0 c   99%   200.64 Mh/s   45 / 0   0.00%   5700 Series   55% (2157)   890 Mhz   300 Mhz   1.1v
1   us1.eclipsemc.com
   64.0 c   99%   201.17 Mh/s   43 / 0   0.00%   5700 Series   55% (2149)   890 Mhz   300 Mhz   1.1v

Testing out 890 @ 1.1v, so lower voltage and faster clocks.

Power draw down to 181-183 Watts at wall.  MHash is staying between 400-402, so I've improved my MHash per watt from 2.0 to 2.2,  not bad, hopefully it stays stable, cross fingers.

I'll buy the cards when you give up mining with them. :P

If you could get ~ 30 of those machines it would be a good income per month.
But that would require quite an investment and I don't think you can get the parts at those prices any longer :)

1322 total accepted shares
18 total invalid shares
1.343% reject ratio

Would that indicate the OC is a bit too high with 1.3% invalid?

It might be, I'm running my 5770 at 900 with stock voltages and I get very low invalids.  Getting around 220 Mh/s

18985 / 11 / 0 / 0   0.06

Thanks for sharing.

I was running 900 mhz too, but at 1.1v instead of the stock 1.2v, so that's a pretty big difference.  I lowered it down to 880, I'll see what happens.

Edit: looks like it was the pool.

Changed pools and my rejects went down, even at higher clocks. so far up to 914MHz at 1.1V  :o

Miner:   Phoenix
Temp:   64.0 c
Load:   99%
Shares A/R:   2269 / 3 (0.13%)
GPU family:   5700 Series
Fan speed:   55% (2157 rpm)
Core clock:   914 Mhz
Mem clock:   300 Mhz
Core power:   1.1v

This is a great value build, well done sir.