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you're looking for a half-lengh case, such as
https://www.bhphotovideo.com/c/product/ ... _se_i.html
Raphaël Jacquot wrote:you're looking for a half-lengh case, such as https://www.bhphotovideo.com/c/product/ ... _se_i.html
Dave Del Vecchio wrote:One thing worth noting about Thunderbolt 3 and Thunderbolt 4 is that even though these ports are theoretically capable of 40 Gbps of bandwidth, the data transfer channel uses a PCI Express 3.0 x4 interface which is limited to around 32 Gbps of bandwidth. To fully saturate the 40 Gbps interface of a Thunderbolt 3 or 4 port would require something like DisplayPort output (as that is separate from the 32 Gbps data channel).
This data transfer bandwidth limitation has implications when daisy chaining multiple Thunderbolt devices or when using a multi-slot PCIe Thunderbolt enclosure. Because effectively all of those PCIe slots (or devices) connected to that Thunderbolt port are sharing the same 32 Gbps PCIe 3.0 x4 interface into the computer. And in fact even a single PCIe card could exceed the available bandwidth if it uses a PCIe 3.0 x8 or x16 interface and actually uses that much bandwidth.
For a lot of PCIe cards, this bandwidth sharing may not be a huge issue (which is why manufacturers put x8 or x16 slots in those enclosures to begin with). Things may slow down if there is bandwidth contention, but storage, network, graphics will often still work fine, just perhaps not as fast as if more bandwidth were available. For video capture or playout cards though, where you need frames to be processed at a certain rate, these types of bandwidth limitations can be problematic.
Dave Del Vecchio wrote:And with Thunderbolt 3 specifically, things are sometimes even a bit worse than this, because the Thunderbolt 3 specifications allow computer hardware manufacturers to use either a PCIe 3.0 x4 (32 Gbps) or a PCIe 3.0 x2 (16 Gbps) interface to the port. And some laptop vendors (including Dell and others) opted for the slower PCIe x2 interface for their Thunderbolt 3 ports on some models.
With Thunderbolt 4, a PCIe 3.0 x4 interface (32 Gbps) to the port was made required rather than just being optional as it was with Thunderbolt 3.
Dave Del Vecchio wrote:So especially with multiple streams of higher frame rate 4K 50fps/60fps video which is 12 around Gbps at the SDI interface (but may be a bit less when going between the capture card and computer, depending on the frame and pixel format used), it's certainly possible to exceed the 32Gbps bandwidth of the Thunderbolt data channel.
Dave Del Vecchio wrote:Some additional background on Thunderbolt interface and bandwidth in this tech brief:
https://www.thunderbolttechnology.net/s ... _FINAL.pdf
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