Looking for Smallest Possible eGPU Mainboard
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Looking for Smallest Possible eGPU Mainboard  


New Member
Joined: 4 years ago

Hi everyone!

I am a small form factor enthusiast who loves trying to stuff the fastest hardware in the smallest possible enclosures. For my newest project, I am currently working with a known (at least in the SFF community) case manufacturer to try to design the smallest possible eGPU enclosure that provides at least 65w of charging and at minimum with an internal PSU, and at least 2 usb ports for peripherals. We are aiming at keeping it significantly under the Aorus Gigabyte Gaming Box's 3.3 liters, and by my early estimations are that we should be able to get to somewhere around 2.6 liters, although I am trying to get it even smaller which is why im asking the community for help.

I have purchased, shucked and tested a number of enclosures, and right now I am having a hard time finding anything decent that fits the needs listed above. Does anyone know of any mainboards that fit the specifications I require? The smallest I have found that has both the USB ports and meets charging requirements is from the Manitz Saturn Pro which measures at 25cm x 11cm. Height is somewhat irrelevant as the pcie riser we use will likely be the biggest variable there. That board also has a horizontal power connection, which will jet out significantly past the 180mm GPUs we are trying to keep as the maximum length for the case. The power pins can be re-soldiered into a vertical orientation, but I'd like to release the CAD files to anyone who'd like to replicate the build when we are done, and I'm sure that will turn off most people from attempting to copy the build.


To do: Create my signature with system and expected eGPU configuration information to give context to my posts. I have no builds.


Reputable Member Moderator
Joined: 3 years ago

There are some pretty interesting eGPU PCB's available through the Taiwanese technology market. They often make their way to TaoBao, Bangood and Aliexpress. Here is an example of one:


No USB HUB, and I am unaware of the power delivery:


Small board footprint:

O1CN01o6fGrK1Tz3j7etM7g !!671432452


AliExpress Link to the above board.

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itsage liked
Founder Admin
Joined: 6 years ago

The smallest Thunderbolt 3 board with a x16 PCIe slot is TUL mini eGFX. PD can be changed through Intel TBT certification process. It's best to contact TUL imo and work with them rather than buying off-the-shelf eGPU enclosure to extract the board.

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New Member
Joined: 4 years ago

@itsage, that one is fairly small, but I can tell just by looking at it that its significantly longer than this Manitz i have here unfortunately. It also has a barrel plug which is a bit less desirable, as I am planning on using power supplies from HDPlex to keep the power supply internal and slim it down significantly vs something like a Flex-ATX unit. Still, I’ll probably pick it up for testing. 

This first one will just be a one-off project for now, which is why im not trying to get a pcb designed or anything like that just quite yet.


To do: Create my signature with system and expected eGPU configuration information to give context to my posts. I have no builds.