eGPUs - Thoughts? - Skull Canyon NUC with Thunder3 PCIe Box.

Runamok81

Runner of Moks
Original poster
Jul 27, 2015
446
622
troywitthoeft.com
Ever get an idea and just can't sleep until you try it? Looks like curiosity got the best of me. I've got to alteast try and see if TB3 1070 eGPU is possible. Just received the Gigabyte Mini ITX Gigabyte 1070. If anyone has any requests for measurements, please let me know. Photos below..





The PCB is 170mm.



However the shroud overhand isn't nearly as pronounced as it is in photos. That may not need to be removed. We'll see, the AKiTIO Thunder 3 and HDPlex 160W are on the way and will be here next week. Currently searching for some low-profile PCIe 8-pin connectors, and something to convert the HDPLEX AC-DC output to 8-pin PCIe, any suggestions?
 
Last edited:

Runamok81

Runner of Moks
Original poster
Jul 27, 2015
446
622
troywitthoeft.com
Maybe cut up the second extension to get the extra 2 pins on the GPU side? You'll have to figure out something on the other end to get it connected to the HDPLEX though.

http://www.ebay.com/itm/PAIR-OF-PCI...920862?hash=item3cdb84561e:g:8ZcAAOxyRhBS4CMH

For low-profile 8-pin, you can search eBay, but you can mod one too.

Perfect. Thanks for the links @Phuncz and @Aibohphobia, I will look check those out. Looks like ModDIY has a low profile 8-pin set too?



Has anyone tried that set? Recommended?
 
Last edited:

MrNintend0

Trash Compacter
Jul 15, 2016
35
26
Forgive me if this seems stupid, but what about taking the NUC board and putting it in a slightly larger external PCIE box? Essentially it would just be a case designed for an NUC board with a full size expansion slot afterwards, but if you could tie the NUC board into the HDPLEX for power, you'd just need to worry about one power brick and one case: smaller footprint + less clutter = SFF win. I thought about doing this myself in a custom case, but decided it wasn't worth it. Cool project, yes. Useful for me, not likely... I've got enough computers as is... Would be better if you could use an MXM card with at least a single display out though...
 
  • Like
Reactions: Soul_Est and Phuncz

jeshikat

Jessica. Wayward SFF.n Founder
Silver Supporter
Feb 22, 2015
4,969
4,783
That's basically what I'm doing in my STX160.0 build log except I'm using a Mini-STX motherboard with a M.2 to PCIe x4 slot adapter instead of a NUC and Thunderbolt 3. Plus the power brick will be internal too :)

With a NUC it could maybe be possible to build a 2.0L box but I wanted a socketed CPU for upgrade flexibility.
 
  • Like
Reactions: Soul_Est and Phuncz

MrNintend0

Trash Compacter
Jul 15, 2016
35
26
I saw that, thought it was cool! Wish I had the time and the resources to do something that complex, but alas I do not and must make use of what I can do/use. Ah well, I'm content either way, got an M1 build I need to finish anyways.
 

Runamok81

Runner of Moks
Original poster
Jul 27, 2015
446
622
troywitthoeft.com
Forgive me if this seems stupid, but what about taking the NUC board and putting it in a slightly larger external PCIE box? Essentially it would just be a case designed for an NUC board with a full size expansion slot afterwards, but if you could tie the NUC board into the HDPLEX for power, you'd just need to worry about one power brick and one case: smaller footprint + less clutter = SFF win. I thought about doing this myself in a custom case, but decided it wasn't worth it. Cool project, yes. Useful for me, not likely... I've got enough computers as is... Would be better if you could use an MXM card with at least a single display out though...

Placing a NUC into an eGPU chassis with an MXM card is a novel idea. But, a proper eGPU needs to have it's own power source. If you tied that GPU together with the CPU via a single PSU, well... then... you'd no longer have an eGPU chassis, would you? You'd have a PC. As Aibo pointed out, Mini STX is really the better candidate there.

No, let's not strip the eGPU of its major advantage. One GPU for many machines. Sure, the device you're describing would be incredibly small and efficient, but it's also incredibly niche. I'm concerned a device like that would run the real risk of embracing all of the compromises that NUC and MXM boards represent for the sake of size: High price, low availability, and capped performance (soldered CPUs and GPUs limited to 100W).

TB3 technology is spreading fast. Most of the big players are taking GPUs forward by thinking "Outside the box." Asus, MSI, Gigabyte, PowerColor, Acer, Dell, and Razer are all releasing eGPU products this year. While those products are for full-size cards, all of the most popular cards have a mini variant. Until we have a Mini-STX board with TB3, I think Mini eGPU over TB3 makes a lot of sense for quite a few folks. At least until PCIe 4.0 and OCuLink take hold.
 
Last edited:

Hahutzy

Airflow Optimizer
Sep 9, 2015
252
187
Ever get an idea and just can't sleep until you try it? Looks like curiosity got the best of me. I've got to alteast try and see if TB3 1070 eGPU is possible. Just received the Gigabyte Mini ITX Gigabyte 1070. If anyone has any requests for measurements, please let me know.

Could you check the following measurements for me:

1) Bottom of pcie x16 connector to top of PCB
2) Bottom of pcie x16 connector to top of 8-pin connector (or does the 8-pin land just at the same height as the PCB?)
3) Bottom of pcie x16 connector to top of card (shroud?)
4) Width-wise, does the card exceed the dual-slot bracket? I saw some pictures showing it's just a bit fatter.

Thanks, excited to see your testing with TB3!
 

Runamok81

Runner of Moks
Original poster
Jul 27, 2015
446
622
troywitthoeft.com
Could you check the following measurements for me:

1) Bottom of pcie x16 connector to top of PCB
2) Bottom of pcie x16 connector to top of 8-pin connector (or does the 8-pin land just at the same height as the PCB?)
3) Bottom of pcie x16 connector to top of card (shroud?)
4) Width-wise, does the card exceed the dual-slot bracket? I saw some pictures showing it's just a bit fatter.

Thanks, excited to see your testing with TB3!

@K88D has you covered for dimensions on the GTX 1070 Mini ITX OC - his measurements below.



I'm hoping to continue, but I may have hit a snag. Someone please chime in if they have advice.

Issue. I'm currently trying to figure out if powering the AKiTiO and the GPU is feasible? The product listing says dual, but in every picture I see the HDPLEX 160W AC-DC only has a single ATX 12V 4-Pin out? That's only two 12V leads? I'm not we can wire that into a PCI-e 8-Pin connector AND power the board itself. I'd love to not have to use a power brick.

 
Last edited:
  • Like
Reactions: Hahutzy

jeshikat

Jessica. Wayward SFF.n Founder
Silver Supporter
Feb 22, 2015
4,969
4,783
Looks like the HDPLEX only has an ATX 12V 4-Pin out? Not sure how best to wire that to PCI-E 8-pin on the GIgabyte card.

I believe the stock HDPLEX 250W PCIe cable doubles up one of the GND wires from the PSU side for the 8-pin.

You could either wire something up yourself or buy an adapter like this: https://www.amazon.com/dp/B001TK3TJY/?tag=theminutiae-20



I'm not endorsing that particular adapter, I'm just linking it as an example
 
  • Like
Reactions: TinyAudio

BirdofPrey

Standards Guru
Sep 3, 2015
797
493
Are all USB 3.1 Type C Thunderbolt 3 compatible ?
Nope, in fact, USB-C doesn't even have to be USB 3.1 compatible.

USB-C has a few wire groupings:
  • USB 2.0: required, and rotationally symmetric so it can't be pluged in backwards (the receptacle has two sets, while the cable only has one).
  • CC: (configuration channel), used for cable detection and link/power configuration one pin/wire of which becomes mapped to VCONN to power cable electronics (for active or electronically marked cables), also required and also rotationally symmetric, though one pin can be replaced with another use where the device can't be plugged in backwards such as device docks.
  • 4 twisted pair links: USB 3.0 and 3.1 uses two for TX and RX with mapping auto-negotiated when plugged in. USb alt mode specified in the Power Delivery 2.0 spec allows other uses, so far there is DisplayPort, MHL, and Thunderbolt, and they can be dynamically mapped (so you could use 2 lanes for USB 3.1 and the other two for Displayport or thunderbolt, etc., or use all of them for just displayport or thunderbolt, etc.)
  • VBus: provides power to devices, power can be provided either to the device or the host, or to the host from the device; maximum power is 100W at 20 V (5A) auto-negotiated on plug in.
  • Sideband: an alternate data path for other, non-USB uses. (eg. Displayport alt mode would use this for the Aux channel)

There's also an alternate mapping that routes headphone and microphone signals to certain pins, so could presumably be used instead of TRRS connectors for headsets.

The only thing that is actually required by the USB3.0 specification is the USB2.0 and cable detection/VCONN pins/wires. Everything else is optional, and requires a controller for that mode, so USB 3.1 requires a USB 3.1 root hub, thunderbolt requires a thunderbolt controller, etc.
Now as far as I can tell, most thunderbolt 3.0 hosts also have a USB 3.0 root hub on their type C ports, but the reverse isn't true.

There's also some cable differences. Thunderbolt 3 can use standard USB-C cables, but has to reserve specific TX and RX pairs, so effectively halves the bandwidth, but the cables are cheap. You can also use active cables, either copper or optical, where the cable electronics mange signal crashes to allow duplex operation over all 4 links, but the cables cost more, of course.
 
Last edited:
  • Like
Reactions: jØrd

Runamok81

Runner of Moks
Original poster
Jul 27, 2015
446
622
troywitthoeft.com
I believe the stock HDPLEX 250W PCIe cable doubles up one of the GND wires from the PSU side for the 8-pin.

You could either wire something up yourself or buy an adapter like this: https://www.amazon.com/dp/B001TK3TJY/?tag=theminutiae-20

Yeah, the HDPLEX connector certainly looks like they just jump over for the two extra grounds on the 8-Pin. That makes sense, but I'm not using an HDPLEX 250W. My intention was to forego the laptop power brick altogether and use the HDPLEX 160W AC-DC NanoPSU.

I clarified the issue in my previous post. I just don't see how I can wire the NanoPSU to the GPU and power the Tunderbolt card in the Thunder3 box. Hmmmm...
 

jeshikat

Jessica. Wayward SFF.n Founder
Silver Supporter
Feb 22, 2015
4,969
4,783
That makes sense, but I'm not using an HDPLEX 250W.

Sorry, wasn't clear. You're not using the 8-pin CPU so you could use that for the PCIe. And if you borrow a GND from the 24-pin for the last GND on the 8-pin you wouldn't have to pigtail off the 8-pin either:



So just jumper the Power On pin to keep the unit on. This way you don't have to splice wires, just rearrange them. Of course I'm assuming this will work. I'm not responsible if you try this and the HDPLEX implodes and opens a portal to the underworld or anything like that.