Prodesk 400 G5 Desktop Mini Flex IO

[SilentStv]

I just bought a used Prodesk 400 G5 Desktop Mini intending to hook up three monitors to it. The model I found only has the two built-in Displayports, and the Flex IO port is empty and unused. One of the benefits of this model is that you're able to switch up that Flex IO card with whatever you want to get VGA, HDMI, a third displayport, or a USB-C 3.1 gen 2 port. Even HPs marketing docs for this model pumps up the available Flex IO port feature.

I'd like to put USB-C or at least an HDMI port, but I can only find 2018 official documentation for HPs v1 Flex IO cards. The docs are all older than the Prodesk 400 G5 DM though, and they all indicate the Prodesk 400 G4 DM as the maximum supported system.

The faster v2 Flex IO card documents all indicate that they're compatible with the Prodesk 400 G6 Desktop Mini.

Every retailer shows the exact same official HP generic info (Newegg, CDW, Amazon, etc)... v1 for the G4, v2 for the G6, but nobody and nowhere has an answer on what version the G5 actually uses. Even Partsurfer fails to list a single Flex IO part number to use with the G5 Mini despite the fact that they're prebuilt with them on the regular.

So what gives? What part numbers are compatible with the Prodesk 400 G5 Desktop Mini for HDMI and for USB-C? Does it take the older v1 cards, or the newer v2? Help!  

[DGroves]

the flex I/O cards are not interchangeable, the v1 has a chunk of area missing  on the board to clear existing chassis parts

the v2 board is a simple square circuit board

here's a link showing both HDMI cards  the main pict is a v1 and the top left is the v2

https://www.amazon.com/HDMI-Flex-400-600-800/dp/B07GBF1S6Y

The HP HDMI Port Flex IO (400/600/800) is compatible with the HP ProDesk 400 G5 Small Form Factor PC; HP ProDesk 400 G5 Microtower PC; HP ProDesk 400 G4 Desktop Mini PC; HP ProDesk 600 G4 Microtower PC; HP ProDesk 600 G4 Small Form Factor PC; HP ProDesk 600 G4 Desktop Mini PC; HP EliteDesk 800 35W G4 Desktop Mini PC; HP EliteDesk 800 65W G4 Desktop Mini PC; HP EliteDesk 800 95W G4 Desktop Mini PC; HP Collaboration PC G4

[SilentStv]

Thanks, I really appreciate the effort, but all this unfortunately just repeats what I already know. If I thought v1 and v2 were interchangeable, I'd just order one of them and wouldn't be here asking for help clarifying which one is the actual model for the G5, since no retailer and not even HP seems to have that info documented.

Based on your own answer, the v1 description from Amazon indicates it's compatible with the Prodesk 400 G4 DM (desktop mini).

If you look up the v2 cards, HP and retailers state Prodesk 400 G6 DM

I have a G5 right in the middle of those two. Neither Flex IO model is documented as being compatible by HP or by retailers. This includes the documentation for the cards, and for the PC model itself.

I'm leaning 99.9% towards it being the v1 cards based on a brief glimpse of one in a G5 teardown video, but I'm here looking for a definitive answer because I can't throw $70 at a non-refundable hunch while HPs documentation and Partsurfer completely drop the ball on identifying the right model to use with PD 400 G5 DMs.