Using other cards in the slot for PERC

Hi. Sorry to bump the thread, but I need to know if it's possible to use other cards in the dedicated PCIe-slot for PERC?

I kind of have plans for my PowerEdge 1950 Mk II-server.

I'm thinking of possibly expanding the number of drives and use a number of SATA-cards by using a PCIe-expander to a separate chassie. I'm currently using the PERC 5/i-card with SAS->SATA-connectors, but it's giving me a hard time with "Press F1 to continue".

That's quite annoying and I haven't tried disabling it in BIOS yet, but that's no immediate concern right now as I'm, as I said above, thinking of expanding it with much, much more disk drives.

I'm thinking of using the two existing PCIe X8-slots for a GPU as well as one WiFi-card and the PERC-slot for the PCIe-expander via USB 3-cable.

So, question is, would it work or would the server tell me to take a hike..?

I don't have any PCIe-expanders to test this with, and I'm still looking for an X8-version so that I might have some more bandwidth too.