Mobo to support four RX480s

[r0otctrl]

I'm thinking about putting together a crypto-currency mining rig, so I was wondering are there any motherboards that support 4-way crossfire and x16 capability on more than only one PCI-e slot?!

I plan on using RX480s.

[RGProductions]

Cryptocurrency is not worth it.

[Space Reptile]

first of all i would not recommend coin mining in this day and age at all , but if you insist 

here are a few

 

• Gigabyte GA-Z170X-Gaming G1

• Asus Z97-WS ATX

 

 

 

[ARikozuM]

Mining doesn't utilize Crossfire... They share the load but not through SLI.

[SnowyMus]

12 minutes ago, r0otctrl said:

I'm thinking about putting together a crypto-currency mining rig, so I was wondering are there any motherboards that support 4-way crossfire and x16 capability on more than only one PCI-e slot?!

I plan on using RX480s.

First of all, it's not going to be very efficient using either Crossfire or SLI for computational reasons. You're better off running them independently. In fact, this is why projects like Folding@Home do not use either.

 

If you don't want to use some sort of riser, many EATX boards will support four dual-width graphics cards if this is what you're looking for. They're quite expensive, though, with many of them priced over $400 if you're going X99.

 

Otherwise, there are many ATX boards with four x16 slots, though you may not be able to fit all four of them on the board without modding, so you're likely going to be using some sort of riser.

[r0otctrl]

It's still profitable if you join a pool with a decent fee. I'm profiting just from mining on an R9 380 and i5-4690k, but obviously I'd prefer avoiding the wear and tear on the hardware of my main system.

I'm probably not even going to mine with GPUs, but ASICs. However, I'm just exploring my options right now...

 

1 hour ago, ARikozuM said:

Mining doesn't utilize Crossfire... They share the load but not through SLI.

Ah, you're right. Now that I think of it I haven't seen anybody utilizing crossfire in their GPU rigs. Thanks so much

1 hour ago, Kavawuvi said:

First of all, it's not going to be very efficient using either Crossfire or SLI for computational reasons. You're better off running them independently. In fact, this is why projects like Folding@Home do not use either.

 

If you don't want to use some sort of riser, many EATX boards will support four dual-width graphics cards if this is what you're looking for. They're quite expensive, though, with many of them priced over $400 if you're going X99.

 

Otherwise, there are many ATX boards with four x16 slots, though you may not be able to fit all four of them on the board without modding, so you're likely going to be using some sort of riser.

If I do go the GPU route instead of ASICs, I will be buying the cheapest CPU available. Of course I will also want to find the cheapest mobo that supports four GPUs, ideally at x16 for each slot. Haven't found a mobo that allows that yet. Usually it'll run one GPU at x16 and a second at x8 or x4, and probably even less for additional GPUs.

[Megah3rtz]

why not buy a single titan XP? assuming you are buying this (if not, I recommend this one) http://www.newegg.com/Product/Product.aspx?item=N82E16814150773 

4 of them would be 1,100$ anyway ,and a tian for 1,200

[ARikozuM]

1 minute ago, Megah3rtz said:

why not buy a single titan XP? 

Mining benefits from multiple workers being independent. Usually.

[r0otctrl]

1 hour ago, Megah3rtz said:

why not buy a single titan XP? 

Because a single Titan is barely more efficient than a single RX480 at mining BC.

1 Titan = 36% efficiency of 4 RX480s, for roughly the same price.

1 hour ago, Space Reptile said:

first of all i would not recommend coin mining in this day and age at all , but if you insist 

here are a few

• Gigabyte GA-Z170X-Gaming G1

• Asus Z97-WS ATX

Holy smokes that GB mobo is ridiculously expensive -.-

[SnowyMus]

20 minutes ago, r0otctrl said:

If I do go the GPU route instead of ASICs, I will be buying the cheapest CPU available. Of course I will also want to find the cheapest mobo that supports four GPUs, ideally at x16 for each slot. Haven't found a mobo that allows that yet. Usually it'll run one GPU at x16 and a second at x8 or x4, and probably even less for additional GPUs.

I suppose this depends.

 

If you go X99 and get a CPU that has 40 PCIe lanes (which is expensive), it'll run one at x16 and three at x8, which is about as good as it gets.

 

If you do Z170/Z97/Z87, it'll run one GPU at x8 and the remaining three at x4, with the fourth one using the chipset lanes, as Z170 doesn't support 4x4 for graphics PCIe lanes.

 

If you use H170 or B150, it'll run one GPU at x16 and the remaining three at x4 using chipset lanes and will very likely bottleneck each other as a result. H170 and B150 do not support dividing graphics PCIe lanes.

 

If you use an AM3+ socket, the AMD 990FX chipset provides 32 lanes and supports configurations of 4x8. However, you're also limited to PCIe 2.0, so this is equivalent to PCIe 3.0 4x4.

[r0otctrl]

2 minutes ago, Kavawuvi said:

I suppose this depends.

 

If you go X99 and get a CPU that has 40 PCIe lanes (which is expensive), it'll run one at x16 and three at x8, which is about as good as it gets.

 

If you do Z170/Z97/Z87, it'll run one GPU at x8 and the remaining three at x4, with the fourth one using the chipset lanes, as Z170 doesn't support 4x4 for graphics PCIe lanes.

 

If you use H170 or B150, it'll run one GPU at x16 and the remaining three at x4 using chipset lanes and will very likely bottleneck each other as a result. H170 and B150 do not support dividing graphics PCIe lanes.

 

If you use an AM3+ socket, the AMD 990FX chipset provides 32 lanes and supports configurations of 4x8. However, you're also limited to PCIe 2.0, so this is equivalent to PCIe 3.0 4x4.

 

http://www.newegg.ca/Product/Product.aspx?Item=N82E16813132126

PCI-E gen 3.0 // 4 (single at x16 , dual at x16 / x16 , triple at x16/ x8/ x8, Quad at x8/ x8/ x8/ x8)

Pretty solid for the price.

[ARikozuM]

Just now, r0otctrl said:

 

http://www.newegg.ca/Product/Product.aspx?Item=N82E16813132126

PCI-E gen 3.0 // 4 (single at x16 , dual at x16 / x16 , triple at x16/ x8/ x8, Quad at x8/ x8/ x8/ x8)

Pretty solid for the price.

You need a CPU that can handle the lanes.

[SnowyMus]

19 minutes ago, r0otctrl said:

 

http://www.newegg.ca/Product/Product.aspx?Item=N82E16813132126

PCI-E gen 3.0 // 4 (single at x16 , dual at x16 / x16 , triple at x16/ x8/ x8, Quad at x8/ x8/ x8/ x8)

Pretty solid for the price.

 

18 minutes ago, ARikozuM said:

You need a CPU that can handle the lanes.

There aren't any Z97-compatible CPUs that have more than 16 lanes.

 

From doing some Googling around, how it works is it switches the 16 lanes between the slots using a PLX switch. Technically, 16 lanes are still being used at most.

[r0otctrl]

32 minutes ago, Kavawuvi said:

 

There aren't any Z97 CPUs that have more than 16 lanes.

 

From doing some Googling around, how it works is it switches the 16 lanes between the slots using a PLX switch. Technically, 16 lanes are still being used at most.

I'm confused. Why would your CPU need more than 16 lanes?

[SnowyMus]

23 minutes ago, r0otctrl said:

I'm confused. Why would your CPU need more than 16 lanes?

Physically, you can only expand your computer with so many PCIe devices.

 

With Intel CPUs, lanes for graphics cards come from the CPU. The chipset itself does have lanes, but it's limited to 4 lanes per device, and the interface between the chipset and CPU only supports up to 4 lanes of bandwidth. On an X99 motherboard, this really isn't a problem, as you have tons of lanes on your CPU (28 or 40 lanes), while the lanes on the chipset are pretty irrelevant. On non-enthusiast CPUs, you only get 16 lanes from the CPU.

 

On the AMD FX platform, all of the lanes are still handled by the chipset's northbridge (I say "still" because Intel used to handle it like this), while the CPU itself doesn't have any lanes, so in that case, your CPU wouldn't need any lanes.

 

The motherboard you picked has a PLX chip which effectively switches these 16 lanes between the PCIe slots. It's not quite the same as having 8 lanes dedicated to each slot, as it's really dedicated to two slots, but the two slots they're dedicated to changes.

[r0otctrl]

37 minutes ago, Kavawuvi said:

Physically, you can only expand your computer with so many PCIe devices.

 

With Intel CPUs, lanes for graphics cards come from the CPU. The chipset itself does have lanes, but it's limited to 4 lanes per device, and the interface between the chipset and CPU only supports up to 4 lanes of bandwidth. On an X99 motherboard, this really isn't a problem, as you have tons of lanes on your CPU (28 or 40 lanes), while the lanes on the chipset are pretty irrelevant. On non-enthusiast CPUs, you only get 16 lanes from the CPU.

 

On the AMD FX platform, all of the lanes are still handled by the chipset's northbridge (I say "still" because Intel used to handle it like this), while the CPU itself doesn't have any lanes, so in that case, your CPU wouldn't need any lanes.

 

The motherboard you picked has a PLX chip which effectively switches these 16 lanes between the PCIe slots. It's not quite the same as having 8 lanes dedicated to each slot, as it's really dedicated to two slots, but the two slots they're dedicated to changes.

Interesting. Soooo AMD boards are capable of handling multiple GPUs at more lanes per each card?

[SnowyMus]

47 minutes ago, r0otctrl said:

Interesting. Soooo AMD boards are capable of handling multiple GPUs at more lanes per each card?

If we're talking about the boards themselves, then sure. However, AMD's 9-series chipsets (the chipsets used for current FX processors) are limited to PCIe 2.0 (it's that old), so you're getting effectively half the bandwidth you would normally get with PCIe 3.0. If you're using a board that uses the 900 FX chipset, which has 32 PCIe 2.0 lanes provided by the northbridge, you can get a 4x8 configuration, but that's equivalent to a 4x4 PCIe 3.0 configuration in terms of total bandwidth.

 

PCIe 3.0 x8 and even PCIe 3.0 x4 isn't necessarily a bad thing, if this is what you're worried about. The speed of the interface won't affect the speed of the card, merely the bandwidth for the card to communicate with the CPU. It only becomes a problem when too much time is spent trying to communicate rather than actually computing anything.

[r0otctrl]

2 hours ago, Kavawuvi said:

If we're talking about the boards themselves, then sure. However, AMD's 9-series chipsets (the chipsets used for current FX processors) are limited to PCIe 2.0 (it's that old), so you're getting effectively half the bandwidth you would normally get with PCIe 3.0. If you're using a board that uses the 900 FX chipset, which has 32 PCIe 2.0 lanes provided by the northbridge, you can get a 4x8 configuration, but that's equivalent to a 4x4 PCIe 3.0 configuration in terms of total bandwidth.

 

PCIe 3.0 x8 and even PCIe 3.0 x4 isn't necessarily a bad thing, if this is what you're worried about. The speed of the interface won't affect the speed of the card, merely the bandwidth for the card to communicate with the CPU. It only becomes a problem when too much time is spent trying to communicate rather than actually computing anything.

I'm not worried. I'm just ignorant. I only started looking into mining a couple days ago. Knew nothing at all about it before then, so of course I've got a lot to learn. I honestly have no idea whether or not one would bottleneck the other because I don't know enough about mining. I think I'm going to be sticking with an ASIC miner to get the ball rolling, though. Thanks so much for sharing all of the info!