Thunderbolt to PCIe x16 Adapters for TrueNAS

[velvia]

Ahoy-hoy,

Long time caller, first time watcher.

I’m in the process of downsizing my workstation and moving my Homeserver (currently TrueNAS) over to it but I’m realizing I’m light on PCIe Lanes for where I’m hoping to eventually take it (Motherboard: Gigabyte B550 VISION D).

Has anyone come across any affordable (read: cheap to the point of questionable quality) TB3 to PCIe x16 adapters/converters/enclosures etc.? I’d like to be able to run a pair to a second enclosure for an HBA and NIC.

I’ve been able to come across enclosures like the Startech TB31PCIEX16 in the ~$250 range. But at that point moving over to an ASRock Rack board makes more sense.

[jeverett]

@velvia

TB3 to PCIe x16 adapters/converters/enclosures etc.? I’d like to be able to run a pair to a second enclosure for an HBA and NIC.

Thunderbolt is x4 PCIe. There’s some non-cheap solutions to chain up two physical x16 enclosures to it, but you’re not only talking big money for rigging something like that up, but you’ll be throttling your HBA and NIC down a shared/serialized x4 PCIe channel a fraction of either of the cards’ bandwidth (which might make sense for a expansion restricted laptop that needs to dock to some extra power sometimes, but it’ll make no sense for a desktop that could just have a different motherboard with more PCIe.)

[Dratatoo]

You could also try to get used Razor Core Enclosure. It seems lots of Mac User who switch to m1 or m2 Macs try to get rid of these.

[jxdking]

When you run out of pcie lines. M.2 slots should be the next thing to look at. m.2 to pcie riser is pretty cheap comparing thunderbolts solution.

[velvia]

@jxdking

When you run out of pcie lines. M.2 slots should be the next thing to look at. m.2 to pcie riser is pretty cheap comparing thunderbolts solution.

The challenge is M.2 is why i’m short on PCIe, this board shares an x4 slot with one of the M.2 slots and I want to use both. If the board didn’t have Thunderbolt this would be less of an issue.

I do have the WiFi slot to play with (What is that, e-key?) but IIRC that’s only x1 and USB.

@jeverett

Thunderbolt is x4 PCIe. There’s some non-cheap solutions to chain up two physical x16 enclosures to it, but you’re not only talking big money for rigging something like that up, but you’ll be throttling your HBA and NIC down a shared/serialized x4 PCIe channel a fraction of either of the cards’ bandwidth (which might make sense for a expansion restricted laptop that needs to dock to some extra power sometimes, but it’ll make no sense for a desktop that could just have a different motherboard with more PCIe.)

x16 Physical, with two TB ports I’d be fine with two enclosures, but like you said a different motherboard seems to be the best option. With AM4 coming down in price swapping the board is cheaper and splitting off “compute” and “storage” workloads might make sense.

[aBav.Normie-Pleb]

Sorry, just saw this topic:

I’ve personally had successful results with making my own little Thunderbolt enclosures by taking the controller board from external TB3-to-M.2 (NVMe/PCIe) adapters and then adapting M.2-to-PCIe Slot. PCIe Gen3 isn’t an issue anymore if the vendor of these adapters is trustworthy.

I don’t think it gets cheaper than that, but works absolutely fine, tested this solution with:

• dGPUs (Radeon VII)
• 10/40 GbE Ethernet Adapters
• HDMI Capture Cards

[jeverett]

@velvia

two TB ports I’d be fine with two enclosures

Typically, two Thunderbolt ports are shared in one x4 PCIe Thunderbolt channel.

Systems like the MacBook Pros with 4 Thunderbolt port have 2 x4 channels, each shared among two of the ports.