Pricing Multi-GPU Rig for sCrypt hashing

[bo122081]

I'm trying to price out a multi-GPU rig for hashing sCrypt. I'm a comp-sci major and I'm A+ certified for hardware, but this is some stuff I haven't really done before (that's why I'm in the newbie forum).

I've been running the numbers, but I'm having trouble figuring out exactly what I need to buy.

My current shopping list is:

Motherboard with 4-8 PCIE slots
3-8 GPUs based on whatever I can find cheapest on this chart I made (https://i.imgur.com/9X4jV0O.jpg)
Powered PCIE risers
PSU(s)
CPU
HDD
RAM

I already have a stack of RAM and several cases (including a large server case), at least 1 spare HDD, and 2 PSUs sitting around.
So, what remains is trying to find an appropriate mobo, and figuring out the total Wattage of the system.

Also, I need to figure out which cards/boards/etc are voltage unlocked....

Uh...HALP!

I'm finding it very difficult to find resources on searching/sorting mobos based on #PCIE slots, and not finding tons of info on what components are voltage unlocked and how that will/could affect the total wattage of the system.

Also, I saw several references to running multi PSU-single-mobo systems - how do you even do that?

Does anyone have a simple guide on who to configure a DIY system like this?

[1715080725]

1715080725

[1715080725]

1715080725

[1715080725]

1715080725

[1715080725]

1715080725

[tuningup]

1200 or 1500 psu is necessary.

[bo122081]

I'm probably going to be starting with 2-4 7950s, so based on that their TDP is 200, but they're voltage unlocked, I was assuming a power draw of somewhere between 350-450 for 2 cards, or 700-900 for 4 - but that's just me spitballin, I have not much clue there. In the past when building systems I'd just kind of ballpark the system, add a healthy cushion in case of later upgrades and go with that.

In the case of mining, though, I feel like I want to go with the bare minimum Watts necessary to keep profitability as high as possibly. I can't remember though, if I had, say, a 1600W PSU, but the system was only drawing ~800W - would the PSU only draw ~800 from the wall, or would it pull more?

Also, I'm still looking for help on choosing a mobo, and any thoughts on multi-PSU systems (I have 2x ~600W PSUs already).

ANY help would be very appreciated on these.

[bo122081]

If I bought a mobo similar to this one (http://www.asus.com/Motherboards/M5A97_LE_R20/#overview), would I have any difficulties fitting a GPU into those 2 PCIEx1 slots on the end of the board (with risers of course), I'm not above cutting and chopping if necessary, but would like to avoid it if possible just for cleanliness/safety reasons.

I'd ideally like to have as many slots as possible for the ability to expand later, but 4 is a decent amount for now. Does anyone know of any 6 or 8 slot boards that are still available? I keep finding links to that big 8slot MSI board, but it's always sold out/out of stock/discontinued.

[bo122081]

Additionally, as you can easily put AMD cards into Intel boards - is there any particular reason to go with an AMD board for this - it seems there's a much better selection of 4+ slot intel boards than AMD...

[lucasjkr]

Additionally, as you can easily put AMD cards into Intel boards - is there any particular reason to go with an AMD board for this - it seems there's a much better selection of 4+ slot intel boards than AMD...

I'm not terribiy impressed with today's compsci majors and have lost all faith in A+ certification...

But FYI there are plenty of amd motherboards with many pci-e slots. 16x or 1x doesn't matter, if you need a riser so be it. But given the price difference between amd and intel gear and that the CPU does nothing but play traffic director for a minimal amount of traffic, I would focus my search in the AMD realm only. My two satoshis

[bo122081]

I'm not terribiy impressed with today's compsci majors and have lost all faith in A+ certification...

Not sure if that's in general, or a specific dig at me. I'm not very far into my major, and A+ certification doesn't really cover mining rigs...
I know I can put an AMD card in an intel board, I was more asking if there's any performance hit from into boards, as their IS a big performance hit with Nvidia cards...
I am also aware the gratuitously slotted intel boards run more expensive, as do the processors, I was just wondering if there was any technical reason to limit my search to AMD boards only - as if I could find a cheap intel board, it might be a good deal...

I also have never dealt personally with PCIE risers before (why would I?), same with multi-PSU rigs...

Mainly, I assume, as this is a mining forum, that there would be a plethora of people here who have SPECIFIC experience and research already done on this that might be willing to share...

So, I'm not really sure where the hostility is coming from...unless I'm mis-reading your comment. If so, I apologize.

[lucasjkr]

No hostility, merely sarcasm.

There's zero performance hit in using AMD add on cards with intel chipsets. The performance gap between AMD and Nvidia is due to their different architectural approaches to doing work; it works out to AMDs advantage in the case of bitcoin, it comes out to nvidias advantage in other cases. But the maker of the board or chipset has no relevance to it.

Meanwhile, opting for intel boards and CPUs means paying the intel premium for no advantage, as the CPU does next to no work in the process. If you're only finding intel boards with many slots, look on other sites, there's plenty of AMD boards with just as many slots out there. If you find an intel board and processor as cheap as and AMD one, go for it. But that generally won't be the case, as that's AMDs lifeblood right there.

[boatase]

I'm trying to price out a multi-GPU rig for hashing sCrypt. I'm a comp-sci major and I'm A+ certified for hardware, but this is some stuff I haven't really done before (that's why I'm in the newbie forum).

I've been running the numbers, but I'm having trouble figuring out exactly what I need to buy.

My current shopping list is:

Motherboard with 4-8 PCIE slots
3-8 GPUs based on whatever I can find cheapest on this chart I made (https://i.imgur.com/9X4jV0O.jpg)
Powered PCIE risers
PSU(s)
CPU
HDD
RAM

I already have a stack of RAM and several cases (including a large server case), at least 1 spare HDD, and 2 PSUs sitting around.
So, what remains is trying to find an appropriate mobo, and figuring out the total Wattage of the system.

Also, I need to figure out which cards/boards/etc are voltage unlocked....

Uh...HALP!

I'm finding it very difficult to find resources on searching/sorting mobos based on #PCIE slots, and not finding tons of info on what components are voltage unlocked and how that will/could affect the total wattage of the system.

Also, I saw several references to running multi PSU-single-mobo systems - how do you even do that?

Does anyone have a simple guide on who to configure a DIY system like this?

Check out coinminingrigs.com. I built my rig based off their instructions and their parts and it works pretty well.  Also, check out the mining section for more info on rig building in general.