Upgrading from PXIe-8840 to Windows 11. Does the PXIe-8822 support the same 8GB/s chassis speed of the 8840, do I need the 8842?

[johngardner58]

Hi,

Our company is switching to Windows 11.    I currently have two racks with the PXIe-8840.   The 8840 controller supports the full backplane speed of my chassis (1082) at 8GB/s.  When looking at the PXIe-8822 it says 2.5TB/s for the pcie link speed which is way faster than 8 GB/s, but I am not sure they are the same thing (which BTW is not useful)    I don't want to lose the backplane speed. Or are they using the right units on the web page.

So the question is, "does the PXIe-8822 support the full 8 GB/s speed of the 1082 chassis".

[Captain_K · Accepted solution]

So, the 8822 can operate at a PCIe link speed of 2.5 GT/s. This is different than 2.5 TB/s. PCIe specs the speed in Transfers per second. 2.5GT/s is about 250MB/s.

Then, we take this speed and multiply it by the number of links the controller can connect with. The 8822 can connect with four x4 links, or two x8 links. This would give a total of 4GB/s.

The 1082 can support 5GT/s (or about 8GB/s with all it's lanes and connections). To match this, I'd recommend going with the PXIe-8842.