Can you run a GPU off a M.2 slot?

Quartz-1

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I've been reading about the Skull Canyon NUCs. They come with two M.2 slots. These slots are PCIe3 x4. So I'm wondering if you could run a GPU off one of them? With a ribbon cable to a x16 slot, that is.

I'm thinking that current might be an issue, but could that be resolved if the card had a supplementary power connector?

How badly would the x4 slot limit a GPU like the GTX 950 or 960?
 

pendragon1

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you should edit your title and add "YES!!" to the end. i knew about the other styles of egpu but I did not know you could do this, it's f'n cool!
also, I saw somewhere else around here that you can use an old xbox psu(203w) to power your gpu really easily. so without any OC you could run a 1080...
 

Quartz-1

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So that's the next [H] case design! Let's face it: a NUC plus a GTX 960 should beat the pants off an XB1 or a PS4.
 

Quartz-1

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So, now we know it's possible, how badly will the x4 slot limit the GPU?
 

Dan_D

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An M.2 slot on a modern motherboard is actually a mini-PCI-Express slot of sorts with 4x lanes. No more, no less. In the past you had SATA type only M.2 slots which weren't necessarily PCIe based, but rather a SATA port in M.2 form. Newer motherboards can handle those drives as well due to SATA Express support which essentially allows backwards compatibility of SATA over PCIe lanes. It's essentially the same as plugging a SATA drive into a SATA Express port. It's PCIe, or rather SATA over PCIe.
 
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Good morning,

Is it possible for m.2 connections to pci-e connections, to video cards, ie for mining purposes? I do not need full 16x capability.
if this is true, some of the new boards will be capable of supporting 9 cards. one I saw has 7 slots, + 2 m.2.'s.

If I am wrong, can you tell me what hardwire I would need to put a graphics card on both m.2 slots? It wouldn't be for gaming, so I don't need the 16x spot. I can use x1 risers for my purposes, son wanted to build a 9 card mining rig.

This is all I need, yea?
https://www.alibaba.com/product-det...60584581427.html?spm=a2700.7724838.0.0.8DQCQR



is this right?

Sincerely,
Squirrel Dog
 

Dan_D

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Firmware and BIOS issues aside, it should work. Theoretically at least. Though keep in mind that it will, or should go through the chipset's lanes.

There is a laundry list of shit that may prevent it from working but at their core, M.2 slots are tiny PCIe x4 slots.
 

SomeGuy133

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PCIe 3.0 x4 is pretty good but PCIe 2.0 x4 is very bad. There is legit loss of performance.

It is highly game dependent but with it is Ultra M.2 it should be half way decent but Thunder bolt would be better choice I think. (could be wrong)
 

chenw

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What about power draw? Can the M.2 safely supply 75W through it to the GPU?
 

Quartz-1

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What about power draw? Can the M.2 safely supply 75W through it to the GPU?

More to the point, if the M2 socket cannot supply enough current, will the card draw the current from the auxiliary power connectors?
 

Dan_D

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What about power draw? Can the M.2 safely supply 75W through it to the GPU?

That's a good question and the answer is "no." I didn't even think of that when I responded earlier. It looks like you'd only get about 25w out of an M.2 slot.

More to the point, if the M2 socket cannot supply enough current, will the card draw the current from the auxiliary power connectors?

I believe so, but you are in a situation where you are beyond the PCIe / ATX power supply specs. While physically possible, it is ill-advised.

Theoretically, the motherboard manufacturer can choose what they'll support via the M.2 connector. Graphics cards are technically possible in some respect but as far as I know, its rarely been done and never tested by any of the major motherboard manufacturers. There is little to no reason to ever do this. You do sometimes see WiFi adapters supported using "unused" pins in the M.2 slot which are reserved for such things but GIGABYTE and or MSI are the only manufacturers I've seen do even that much.
 
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mnewxcv

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Don't some of the adapters have power inputs though? I remember the express card to pcie ones did.
 

Dan_D

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Don't some of the adapters have power inputs though? I remember the express card to pcie ones did.

They very well could and that would solve that problem. Like I said, in theory it should work but in practice, I'll wager its problematic on a lot of motherboards.

PCIe 3.0 x4 is pretty good but PCIe 2.0 x4 is very bad. There is legit loss of performance.

It is highly game dependent but with it is Ultra M.2 it should be half way decent but Thunder bolt would be better choice I think. (could be wrong)

Thunderbolt would be a much better option. It's essentially PCIe via cable anyway.
 

chenw

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My main concern here is not really whether or not the entire 75W can be supplied via the M.2, but does the GPU know if it cannot draw 75W from the slot it is connected to?

Or more precisely, is it able to draw power from its external PCI-E connectors before drawing power from the slot?

This is a non-issue for bus powered cards, so if the GPU cannot draw the full 75W from the slot, then only the very power hungry cards (ironically) can be run this way, as the 50W will be less of a dent on a double 8 pin PCI-E GPU than say 1 6 pin PCI-E card.
 

Dan_D

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My main concern here is not really whether or not the entire 75W can be supplied via the M.2, but does the GPU know if it cannot draw 75W from the slot it is connected to?

Or more precisely, is it able to draw power from its external PCI-E connectors before drawing power from the slot?

This is a non-issue for bus powered cards, so if the GPU cannot draw the full 75W from the slot, then only the very power hungry cards (ironically) can be run this way, as the 50W will be less of a dent on a double 8 pin PCI-E GPU than say 1 6 pin PCI-E card.

Again, cards with external power should be able to do this but you are going to be outside the specs for the card. That's not a good idea.
 

DejaWiz

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Way too much effort, imo. This is going beyond the design parameters of both the M.2 slot and the form factor of the NUC. If the current draw exceeds the operational parameters of the M.2 slots tiny conductors, then bad things WILL happen. You may get lucky and only fry the motherboard and GPU, or you might grab the shit end of the stick and be facing an all out fire. This prompts the age old question: Just because you can, did you ever stop to think if you should?

Don't fuck around with safety...Makes way more sense to simply build a very compact mITX or uATX system in a chassis that is designed to house (and adequately protect) a GPU internally.
 
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