8 HD 5770 GPUs on a Big Bang Marshal?

[Skunkworks]

Topic says it all. Will it work under linux?

I put together a hypothetical parts list that came to about $1800 and 1.7ghash/sec on a single box based around this $400 monstrosity of a mobo.

[1714129849]

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[grue]

waste of money. just get one with enough pci-e x1 slots.

[Capitan]

Yes, it should. I don't know if those are dual-slot cards though, so you might have to work through some issues if they are.

Also, it's more like 1,200Mh/s, isn't it? I thought a single 5770 did about 150MH/s? IMHO it's not worth it unless these cards are $50 each. Even then you just end up getting discounted hardware, that would take several months to pay itself off.

[Coinbuck @ BTCLot]

/facepalm on the last post.

HD5770 can go to 220 mhashes is properly overclocked & with the correct flags.

[bcpokey]

Topic says it all. Will it work under linux?

I put together a hypothetical parts list that came to about $1800 and 1.7ghash/sec on a single box based around this $400 monstrosity of a mobo.

A quick calculation shows that is a horrible rig efficiency. 1.06 $/Mhash ratio (or .94 Mhash/$ ratio)? With declining price, increasing difficulty, you need to become as efficient as possible in your builds, and this is far from it.

As a comparison, back in april I built a 1.7GHash machine, and I spent around $985. Even at 1.73Mhash/$ I still considered it somewhat risky, though it certainly paid off in the end.

Also, be wary of running 8xPCIE cards on a single board, unless you are using risers with power splitters. Even lowly 5770s can pull a lot of power through the board if you use 8 of them, potentially destroying it.

[SgtSpike]

bcpokey, people don't have the luxury of building 1.73Mhash/$1 systems anymore.  It can't be done.

[bcpokey]

bcpokey, people don't have the luxury of building 1.73Mhash/$1 systems anymore.  It can't be done.

Maybe not, that was an exceptionally efficient build that I'm proud of, but it still stands that you need to be very efficient if you want to profit, and < 1Mhash/$ is very inefficient. Even at stable difficulty and $20 coin prices, it wouldn't pay itself off for almost 1.5 months. A bad goal to shoot for.

My point isn't to build my build, I was lucky, it was just that you need to be as efficient as possible, and have numbers to approach, if not asymptotically.

You can still build somewhat efficiently, for example a 4x 6870 rig pulling 1.2GHash/sec can be built for maybe $900 if you build smartly. Already up to 1.333mhash/$. There may be other builds that are more efficient, I'm currently amp capped though so I haven't been looking to build more lately

[gigabytecoin]

You're going to need about 2 * 1200 watt gold PSUs for that beast imho. So that's at least $500 USD.

[Skunkworks]

bcpokey, people don't have the luxury of building 1.73Mhash/$1 systems anymore.  It can't be done.

My most efficient build was right up there, yay for the microcenter markdown bin. 600mhash for $344

Anyway, would the big bang marshal be capable of supporting all 8 of these? The main reason I'm so attracted to making an 8-GPU system is because is because repurposing it is an easy way to drive a 12-16 monitor video wall without messing with (the highly buggy) xdmx.

Also WTF two 1200W psus!? I thought one would do fine!

[bcpokey]

You're going to need about 2 * 1200 watt gold PSUs for that beast imho. So that's at least $500 USD.

for 8 5770s? You're crazy. You don't need 2400 watts to power 8 5870s. A full system with CF 5770s was measured by anandtech as pulling 390W from the wall. Even ignoring the system overhead, 390W * 4 = 1560W. Many people have reported their AX1200s as being able to do that without too much fuss. Not a cheap PSU by any stretch of the imagination, but certainly not $500. More like $250.

Anyway, would the big bang marshal be capable of supporting all 8 of these? The main reason I'm so attracted to making an 8-GPU system is because is because repurposing it is an easy way to drive a 12-16 monitor video wall without messing with (the highly buggy) xdmx.

Again, you run the potential risk of burning out the mobo if you don't provide power bypass for some PCIE slots. They will also need to be single slot 5770s or else you will need to use extenders anyway. If they are not single slot you will need some sort of custom built rig to hold all the cards in place as well. Some things to consider.

Also I still don't have confirmation one way or another, but some users report issues with getting windows to recognize 5+ physical video cards. If you planned on linux anyway not as much an issue.

[gigabytecoin]

You're going to need about 2 * 1200 watt gold PSUs for that beast imho. So that's at least $500 USD.

for 8 5770s? You're crazy. You don't need 2400 watts to power 8 5870s. A full system with CF 5770s was measured by anandtech as pulling 390W from the wall. Even ignoring the system overhead, 390W * 4 = 1560W. Many people have reported their AX1200s as being able to do that without too much fuss. Not a cheap PSU by any stretch of the imagination, but certainly not $500. More like $250.

Anyway, would the big bang marshal be capable of supporting all 8 of these? The main reason I'm so attracted to making an 8-GPU system is because is because repurposing it is an easy way to drive a 12-16 monitor video wall without messing with (the highly buggy) xdmx.

Again, you run the potential risk of burning out the mobo if you don't provide power bypass for some PCIE slots. They will also need to be single slot 5770s or else you will need to use extenders anyway. If they are not single slot you will need some sort of custom built rig to hold all the cards in place as well. Some things to consider.

Also I still don't have confirmation one way or another, but some users report issues with getting windows to recognize 5+ physical video cards. If you planned on linux anyway not as much an issue.

Just because people say that a 1200 can handle 1560 watts.. doesn't mean it's a smart idea.

I like to get more than 6 months out of my $200 PSUs anyways... so I keep them all at 50% load.

[Reikoku]

You're going to need about 2 * 1200 watt gold PSUs for that beast imho. So that's at least $500 USD.

You really don't. A 5770 runs at about 100W, so this would be 800W + 300W system overhead = 1100W continuous. An AX1200 would do this fine.

[bitcoin0918]

I'm curious what calculations you used to determine that you could break even or make a profit with such a setup. What rate of difficulty increase did you assume, and over what period?

[Skunkworks]

I'm curious what calculations you used to determine that you could break even or make a profit with such a setup. What rate of difficulty increase did you assume, and over what period?

I assumed initial depreciation of 0.15*base price for unboxing, then 0.003*base per day thereafter, with mining profitability at a conservative 1.3cent-day per megahash (including electric costs). Giving the profit function including hardware resale where x is in days of (22.1*x)+(1800*(0.997^x))-2070

This gives 16 days in the red assuming hardware liquidation.

Without liquidation, ((22.1*x)-1800) which comes to 81 days.

We're currently at 2.2cent-days per megahash, so this is very conservative calculation wise on mining profits, I'm assuming the worst  

[bcpokey]

You're going to need about 2 * 1200 watt gold PSUs for that beast imho. So that's at least $500 USD.

for 8 5770s? You're crazy. You don't need 2400 watts to power 8 5870s. A full system with CF 5770s was measured by anandtech as pulling 390W from the wall. Even ignoring the system overhead, 390W * 4 = 1560W. Many people have reported their AX1200s as being able to do that without too much fuss. Not a cheap PSU by any stretch of the imagination, but certainly not $500. More like $250.

Anyway, would the big bang marshal be capable of supporting all 8 of these? The main reason I'm so attracted to making an 8-GPU system is because is because repurposing it is an easy way to drive a 12-16 monitor video wall without messing with (the highly buggy) xdmx.

Again, you run the potential risk of burning out the mobo if you don't provide power bypass for some PCIE slots. They will also need to be single slot 5770s or else you will need to use extenders anyway. If they are not single slot you will need some sort of custom built rig to hold all the cards in place as well. Some things to consider.

Also I still don't have confirmation one way or another, but some users report issues with getting windows to recognize 5+ physical video cards. If you planned on linux anyway not as much an issue.

Just because people say that a 1200 can handle 1560 watts.. doesn't mean it's a smart idea.

I like to get more than 6 months out of my $200 PSUs anyways... so I keep them all at 50% load.

A few things of note

1) 1560Watts is Wall power. PSUs are rated to deliver their labelled rating *to the system* (this is after AC/DC conversion). 1560watts (which is higher than the real amount used, I just used it for ease of demonstration) from the wall is ~1300Watts to the system, these are non-underclocked cards to boot, so the real deal will definitely use less power. But regardless, AX1200s are overdesigned to be able to produce that. Yes it is overloading, but if you really really worry about that, drop a $15 cx430 in the mix, solved.

2) lol @ 50% load. That's potentially the most cost inefficient thing I can imagine. Not only are quality PSUs designed to produce 100% of their labelled power (well read the label, 12v will be slightly lower than total), they are designed to do it continuously. That is 24/7/365. That's why a quality PSU comes with a 5 YEAR warranty. The manufacturer knows that they won't have to make good on very many of those warranty claims.

Why not underclock your CPU on your main computer to half clocks so it will last longer? Makes about as much sense to me.

[Skunkworks]

You're going to need about 2 * 1200 watt gold PSUs for that beast imho. So that's at least $500 USD.

for 8 5770s? You're crazy. You don't need 2400 watts to power 8 5870s. A full system with CF 5770s was measured by anandtech as pulling 390W from the wall. Even ignoring the system overhead, 390W * 4 = 1560W. Many people have reported their AX1200s as being able to do that without too much fuss. Not a cheap PSU by any stretch of the imagination, but certainly not $500. More like $250.

Anyway, would the big bang marshal be capable of supporting all 8 of these? The main reason I'm so attracted to making an 8-GPU system is because is because repurposing it is an easy way to drive a 12-16 monitor video wall without messing with (the highly buggy) xdmx.

Again, you run the potential risk of burning out the mobo if you don't provide power bypass for some PCIE slots. They will also need to be single slot 5770s or else you will need to use extenders anyway. If they are not single slot you will need some sort of custom built rig to hold all the cards in place as well. Some things to consider.

Also I still don't have confirmation one way or another, but some users report issues with getting windows to recognize 5+ physical video cards. If you planned on linux anyway not as much an issue.

Just because people say that a 1200 can handle 1560 watts.. doesn't mean it's a smart idea.

I like to get more than 6 months out of my $200 PSUs anyways... so I keep them all at 50% load.

A few things of note

1) 1560Watts is Wall power. PSUs are rated to deliver their labelled rating *to the system* (this is after AC/DC conversion). 1560watts (which is higher than the real amount used, I just used it for ease of demonstration) from the wall is ~1300Watts to the system, these are non-underclocked cards to boot, so the real deal will definitely use less power. But regardless, AX1200s are overdesigned to be able to produce that. Yes it is overloading, but if you really really worry about that, drop a $15 cx430 in the mix, solved.

2) lol @ 50% load. That's potentially the most cost inefficient thing I can imagine. Not only are quality PSUs designed to produce 100% of their labelled power (well read the label, 12v will be slightly lower than total), they are designed to do it continuously. That is 24/7/365. That's why a quality PSU comes with a 5 YEAR warranty. The manufacturer knows that they won't have to make good on very many of those warranty claiicms.

Why not underclock your CPU on your main computer to half clocks so it will last longer? Makes about as much sense to me.

I'm fairly sure power supplies are at peak efficiency operating at 50-75% load, but don't suffer major performance loss above that, only below. I know they are designed to operate at full load 24/7/365 though, the first thing to fail will probably be an electrolytic cap and they're cause for failure is rapid discharging or overvoltage.