P106-90 on old FM1 socket mobo

[smmm]

Hello,

I thought it might be a fun project to make a dedicated folding PC. I'm trying to spend as little money as possible. I was planning on using an old FM1 socket Lenovo motherboard with an AMD A6-3620 and a P106-90 mining card. I think it might be a decent platform for GPU folding, as it has integrated graphics if i plan to use used mining GPUs. I have a concern about the PCIe specifications though. I believe this motherboard only has a PCIe 2.0 16x slot, and I don't know if a P106-90 would be supported by the mobo or have enough bandwidth. Any information on that topic is appreciated.

I also had a second idea for later on if my original plan worked out. I could get a full ATX FM1 mobo (current one is mATX) as they are very cheap, and also buy a second P106-90 to put in a lower slot. I am especially concerned about PCIe bandwidth there, as it's going to have to be split between 2 slots, at 2.0 speeds. This may not be the most efficient strategy, but it does allow me to upgrade down the line, and I always thought a dual GPU system would be cool. I've heard that using Linux over Windows helps give you a bit extra room with the PCIe bandwidth for folding.

I know this mobo/CPU combo isn't ideal, but I just have it sitting around and would like to put it to good use. For all I know, it flat out won't work with a P106-90. What do you think of these ideas?

Thanks.

[bruce]

If I had access to those parts, I'd certainly put them together and try it. It all sounds logical sound IN THEORY. Personally, I have not ordered any new equipment since the mining market collapsed and the P106-* came on the popular markets so maybe somebody with some actual facts and actual experience can respond.

[toTOW]

Don't expect too much from a P106-90 ... it's similar to a GTX 1050 ...

You'll get better results with a P106-100 which is similar to a 1060.

Anyway, I think the minimum requirement in Windows is PCIe 4x ... Linux doesn't have this limitation.

[HaloJones]

Definitely do this on Linux but as said, don't expect much in terms of ppd

[elblat]

I ran a single 1650 on an old FM1 mobo (a75 chipset, PCI-E 2.0x16), A6-3650, and linux for a few weeks and it ran pretty well. Only a little slower than in a modern x570 4.0 slot, averaging 268k vs 306k PPD. So like 10%-15% slower. Didn't try two GPUs on that mobo.

[smmm]

Ok thanks for the information. I looked a prices for used P106-100s, and the ones I found were pretty expensive, around $120 at the cheapest at time of writing. By comparison, P106-90s are around $60. I think I'd want to just try it out at first with the cheapest option considering this is a bit of a weird PC configuration, and then maybe later on if it works out well I could upgrade to a P106-100 or get a second P106-90, which would equal the cost of a 100.

[smmm]

Don't expect too much from a P106-90 ... it's similar to a GTX 1050 ...

You'll get better results with a P106-100 which is similar to a 1060.

Anyway, I think the minimum requirement in Windows is PCIe 4x ... Linux doesn't have this limitation.

When you say the minimum requirement in Windows is PCIe 4x, does that include 4x 2.0, or just 4x 3.0?

[foldy]

It depends on GPU speed. For very slow GPUs pcie 4x 2.0 may be enough but for very fast GPUs you need pcie 8x 3.0 or else it bottlenecks on Windows.

[bruce]

... or you have to accept the fact that your system may be achieving less than optimum performance on big assignments. Certainly a bottlenecked device will be producing a reasonable (or unreasonable, in foldy's opinion ) set of FAH results which is still a lot greater than zero.

One P106-90 is certainly a good start for many assignments and if you then need to upgrade your M/B rather than some other performance change, so be it. I wouldn't push it to two P106-90's or a P106-100.

[toTOW]

By very fast, he means RTX generation ... I think that P106-90 are sufficiently slow to be happy on PCIe 2.0 4x ...

[smmm]

... or you have to accept the fact that your system may be achieving less than optimum performance on big assignments. Certainly a bottlenecked device will be producing a reasonable (or unreasonable, in foldy's opinion ) set of FAH results which is still a lot greater than zero.

One P106-90 is certainly a good start for many assignments and if you then need to upgrade your M/B rather than some other performance change, so be it. I wouldn't push it to two P106-90's or a P106-100.

Ok good to know. However, if toTOW says that a P106-90 is happy on PCIe 2.0 4x, can you elaborate on why you wouldn't do two P106-90s?

For example, a potential FM1 motherboard upgrade I was looking at was a GIGABYTE GA-A75-UD4H FM1, which Gigabyte's specs page lists having a PCIe 2.0 x16 slot and a PCIe 2.0 x8 slot (in an x16 size). My thought process is that you'd have one P106-90 in the top slot, perfect with 2.0 x16, and then later on I could install another P106-90 in the 2.0 x8 slot, which has more bandwidth than toTOW's statement on 2.0 x4, so it would theoretically be just fine as well?

I don't know if the motherboard reduces bandwidth on the slots if you have two cards installed.

[smmm]

By very fast, he means RTX generation ... I think that P106-90 are sufficiently slow to be happy on PCIe 2.0 4x ...

Are the P106-90s good on PCIe 2.0 4x on Windows as well as Linux, or just Linux?

[gunnarre]

For example, a potential FM1 motherboard upgrade I was looking at was a GIGABYTE GA-A75-UD4H FM1, which Gigabyte's specs page lists having a PCIe 2.0 x16 slot and a PCIe 2.0 x8 slot (in an x16 size). My thought process is that you'd have one P106-90 in the top slot, perfect with 2.0 x16, and then later on I could install another P106-90 in the 2.0 x8 slot, which has more bandwidth than toTOW's statement on 2.0 x4, so it would theoretically be just fine as well?

Note that on some some - but not all - motherboards, some of the PCIe slots compete for bandwith with each other or with other connectors on the motherboard (like an M.2 slot); sometimes the slot is even completely disabled by the installation of a device in the competing connector. On this particular board (at least for board rev. 1.0), the x16 slot will go down to x8 bandwith if both PCIe slots are occupied. Sometimes you need to dive into the board's manual to find this out. In this case, the block diagram makes this clear:

So both your cards will get PCIe 2.0 x8 bandwith on this card.
Edit: Re: PCIe Slot Speed - x1 x2 x4 x8 x16

In most cases:
(...)
PCIE 1.1 x16 / 2.0 x8 / 3.0 x4, good enough for GTX 1600 series GPUs under Linux (an RTX 2060 gets 975k PPD in Linux, which is slower than a Core 21 WU), or up to a GTX 1060 in Windows.
(...)

(My emphasis.)

[smmm]

Ok awesome, that's very helpful. I had a feeling it would split up the bandwidth like that. However, in your quote (if I'm understanding correctly), a 2.0 x8 connection is good enough for a GTX 1060 in Windows, and the 1600 series in Linux. Therefore, since the P106-90 is about a 1050 equivalent, it would do just fine with 2 P106-90s on that motherboard in Windows since they're below a 1060, and still getting a 2.0 x8 connection each.

Side question, is there a folding performance benefit to using Linux over Windows, or does Linux just allow you to go below the minimum PCIe requirements of Windows?

[bruce]

is there a folding performance benefit to using Linux over Windows, or does Linux just allow you to go below the minimum PCIe requirements of Windows?

Both, but if you're not familiar with Linux, there's a learning-curve that may not seem worth the small differences.