I am assuming your Dell OptiPlex 5050 is a SFF model, as you have installed a low profile RX560 dGPU.
The Dell OptiPlex 5050 will contain the following USB ports.
- 6 x 3.1 Gen 1 (2 Type-A front/4 Type-A rear) and
- 4 x 2.0 (2 Type-A front/2 Type A rear - 1 front with PowerShare);
- 1 x Internal USB 2.0 header (5-pin header)
The screenshots below show the location, number and type of USB ports present in your Dell 5050 SFF system.
View attachment 565286 Front & Rear ports
View attachment 565287 Internal port for BT (looks like single port connector)
This mean your system has a maximum of 17 USB ports.
They are made up as follows:
- 6 x USB3 physical ports, (Blue tang) should be set with connector type USB3 (3)
- 6 x USB2 virtual ports, (Blue tang) should be set with connector type USB3 (3) as they are served from the USB physical ports.
- 4 x USB2 physical ports (black tang), should be set with connector type USB2 (0).
- 1 x USB2 internal header port on motherboard, should be set with connector type Internal (255).
This means you only need to drop 2 x ports from the total 17 ports available to remain within the 15 x USB Port Limit imposed by Apple.
If you are not using the Internal header port, as you appear to be using and external USB BT dongle, you only need to find one more port to drop.
When undertaking the USB port discovery phase it is much easier to do this when running macOS Catalina. As the XhciPortLimit quirk works in Catalina, but doesn't work in Big Sur 11.3 or newer (including Monterey and Ventura). Using the XhciPortLimit quirk would allow your system to display all 17 ports in Hackintool, on the USB tab.
Obviously you would need to remove your current USBPorts.kext and add USBInjectAll.kext to have all the Skylake USB ports display correctly in Hackintool.
Having the XhciPortLimit quirk enabled would allow you to discover each port, you would need to test each port with a USB2 pen device and then a USB3 pen device. As each port is 'discovered' the port will be highlighted with a Green coloured line in the Hackintool USB tab/window. I use the comments column to describe each port as it is discovered, as shown in the screenshot below from my Coffee Lake system. This lessens the chance of making a mistake when setting each port's connector type. It also makes it easier for someone else to spot any issues.
View attachment 565288 Hackintool > USB tab from CFL system
Ignore the PXSX Fresco Logic USB Controller, ports from this PCIe x1 card don't show in Hackintool.
I would recommend using a spare HDD or SSD to install Catalina 10.15.7 on your system. You would need to make the following edits to your OC EFI to install Catalina.
- Kernel > Quirks > XhciPortLimit change from False/Disabled to True/Enabled
- UEFI > APFS > MinDate change from '0' or '-1' to 20200306
- UEFI > APFS > MinVersion change from '0' or '-1' to 1412101001000000
BlueToolFixup.kext doesn't work in Catalina, so you would need to add the 20.0.0 to the MinKernel entry for this kext if you retain it in your OC setup. So it is not used in a macOS release prior to Big Sur.
You might need to add these three Broadcom kexts to your setup for your Bluetooth USB dongle to work.
- BrcmPatchRAM3.kext
- BrcmBluetoothFirmwareData.kext
- BrcmBluetoothInjector.kext
BrcmBluetoothInjector.kext should be set with MaxKernel entry of 19.99.99, so it is not injected in a macOS release newer than Catalina.
The rest of your OC setup should be fine regards installing macOS Catalina.
Hope this helps.