Bitcoin Forum

I'm debating to sell my rig and extra chassis. This is just a guage for interest....

1 newly built, working mining Rig. The SSD drive would be wiped before any sell.
...Motherboard, MSI 890FXA-GD70
...1200W power supply (good quality)
...SSD Drive
...AMD Anthlon 2
...2G RAM..might be 4G.
...Quantity of 2, Radeon 6990's. (hard to find available anywhere online)
...optical & floppy drive
....4U rack mountable chassis

Also, purchase must include the 9 other 4U rack mountable chassis (almost new condition). No special name brand... they are empty other than that I am pretty sure they all have one optical drive and one floppy drive in each.
One could build a the foundations for a pretty sophisticated mining operation with these 10 chassis.

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The chassis LOOK kind of like this...but just generally: http://www.newegg.com/Product/Product.aspx?Item=N82E16811128064

Conditions:
Buy everything in 'as is' condition....cash only and pick up only (location Temecula, which is north of San Diego on interstate 15).

I'm looking for $3000 for the whole lot.

If I can't sell it all, it will just keep mining. :)

Post replies about your level of interest (if any) or send me an email (see profile).

You weren't very detailed with your parts but I just tried to guesstimate the cost of the machine brand new. I feel like I was extremely generous especially on the ssd.

195-mobo
60-cpu
30-ram
1600-2x6990
30-cd drive
300-ssd
240-psu
60-case
total=2,515

That's brand new. If any one buys this at 3000 they are crazy.

Don't forget the other 9 of the chassis.

if you're looking to sell this dual 6990 mining rig, why are you requiring the buyer to also buy the 9 other cases? you might want to sell the complete mining rig separately from the other 9 chasis

Just trying to get rid of everything. Also, I want to see if the interest is there.

There are nine other chassis (each with CD drive and floppy drive) needed to be include in that calculation.
However, I'm not counting the CD drive or floppy drive in the value. It's part of the chassis from my view. And the SSD drive is maybe $100 (not $300)...so subtract $230.
But still add the nine additional chassis.

Keep in mind, the 6990's are high demand/low supply. They are the highest performance GPU's for mining, and are hard to find avaialble for any timely delivery. As proof, try to find a 6990 that is immediately available online. I haven't checked in a while, but I'd bet you'll find them either sold out, not in stock or weeks from delivery. From just that, they carry more value than retail costs.

As for condition, the system has been used for only a month now. Proven to work. The extra chassis are in excellent condition.

I'm not really sure why some one would want 9 empty chassis. I guess if they plan to expand like crazy but still that shouldn't be included in this price you should just sell that separately if a buyer doesn't want them.

As for the 6990 they are no where to be found but they aren't that spectacular of a mining card. It's ok on electricity and it definitely requires the least amount of space but its megahash per dollar committed to a full server is pretty horrible.

If we went with the cost excluding the 9 extra chassis and including your price cut we have a cost of 2,285. Assuming you get 820 megahash per card thats 1640 megahash.

1640/2285 is .71 megahash per dollar.

An efficient 5830 rig could get 1.36 megahash per dollar so it would cost about 1,205 dollars for the same speed.

2285-1205 = $1080 waisted.

If you live in an apartment or house where electricity isn't included it would still take a very long time to make up for the waisted electricity (upwards of a year maybe even longer I haven't done the calculations)

Who knows the state of bitcoins in a year or more it could be completely gone for all we know or the difficulty could sky rocket. So yes the 6990 may be impossible to find right now but that doesn't mean people should pay more for a used card.

The card's actual value isn't based entirely on how cost efficient it is at mining bitcoins. Though, admittedly those interested in this forum may see it that way.

It's not the most cost efficient card, but it is the most compact GPU for mining. This means (I think so far) that the advantaged cost per megahash for the cheaper cards would be slightly diluted (i.e. from a caluclation as you showed), when you consider the cost of needed hardware to support the cards (e.g. chassis, cpu, mobo...etc..). For example, considering only the card, you might have a cost ratio of 2:1 (where 1 is half of 2), but if you add 0.5 to each side (simulating cost of equal supporting hardware)... the ratio is 2.5:1.5 where 1.5 is more than half of 2.5 - perhaps trivial, but noticeable.

Regardless, considering your points again for this forum, I may reconsider the GPU fraction of the cost...but probably wouldn't sell them below retail.

Also, I will reconsider the requirement of the chassis. They can probably be relatively easily sold seperately on Craigs list.

how much for just the 2 6990s???

so you're forcing the buyer to also buy the other 9 chasis because you need to get rid of them? this is your problem, you shouldn't be putting it on the buyer unless they really want it also. you're already pushing it forcing them to also get the complete rig instead of just the two 6990, but 9 other empty chases... seriously?? sell the rig separately from the 9 empty chasis, you will sell them faster. you even said yourself that the chasis can easily be sold on craigslist, so you do that, shouldn't be the buyer's problem.

having played with the numbers a lot myself, I'm not sure where you get 1.36 MH/$. If you're willing to run open air, and have all your hardware off one motherboard and buy PCI-E extenders, you could run (8-eight) on a single board, but then that decision implies other expenses, like 8 x $25 PCI extenders with power-taps to keep from cooking your motherboard, and framed cases, BIG power supplies, and motherboards that will support 8x PCI-E, all of which add to the bottom line, and offset the savings of the cheap cards.

I put the rough build cost on a machine like that at about $2500 by the time you include EVERYTHING you'd need, which is still around $1.07 $/per/mhash for 2400 Mhash.

In the example you give of a 1600 Mhash, which, at 300Mhash/per/5830, takes 5+ cards (depending on OC levels), which is still $650-$800 worth of cards, depending on your sources.

I'm not saying including the cases isn't hurting the sale, I'm saying that even $1/per/mhash is an aggressive goal.. 6990's have other advantages like Mhash-per-box, but $-per-mhash isn't one of them.

Here is a rough example.
650-5x5830
10-1 gb ram
10-flash drive
75-5*extender cable
30-cpu
195-mobo(probably could go cheaper)
240-psu
60-open frame case made out of aluminum tubing
=$1,270
5 5830's set up in an open frame case can give you close to 330 Mhash
(5*330)/1270=1.29

That was a quick calculation it is in no way the most efficient you can go.

The problem I found with going higher then 5-6 cards is the parts in the server like the mobo and psu get exponentially more expensive so thats the sweet spot.