Catalina Open Core Performance Issues After Changing Computer Components

Not open for further replies.
Jan 12, 2021
ASUS ROG Strix Z490-A Gaming
Intel Core i9 10900k
RX 580
I installed MacOS Catalina via Open Core successfully a few weeks ago, everything was very snappy and responsive. I then realized I needed a Thunderbolt port for Audio Production Interfaces and had to switch my motherboard from an Asus Z490-G to an Asus Z490-A. I swapped motherboards (did NOT reinstall MacOS) and everything booted fine but my performance is really shotty now. Clicking around in applications is laggy and takes a long time to load, I get stutters in even simple video players at high framerates like on, menus are laggy to navigate and I frequently getting the rainbow spin wheel on things that should not need to load, and performance in general just feels lacking compared to what it was when I first installed with my original motherboard. Any ideas as to why this could be happening? Attached is my EFI and specs are below

Intel i9 10900k
RX 580
Asus ROG STRIX z490-A
Samsung 860 EVO 1TB SSD


    2.7 MB · Views: 16


Aug 2, 2013
Gigabyte Z97X-UD5H
HD 4600 / RX 580
  1. iMac
  2. MacBook Air
  3. MacBook Pro
Mobile Phone
  1. iOS
  1. The TB SSDT is for a Gigabyte Titan Ridge, is this the card you installed?
    • Is the Gigabyte card compatible with your Asus motherboard?
    • Shouldn't you be using the Asus TB3 card?
    • Did you first boot into Windows to make sure the TB cards Firmware was updated, before booting in to macOS
    • This firmware update is a common requirement for TB cards working in macOS.
  2. Have you tried running the revised system without the TB card & SSDT installed, what difference does it make?
  3. Did you use the ClearNvram tool on the OC picker or GUI screen, before you booted the system with the new motherboard?
    • This tool is not present in the /EFI/OC/Tools folder, so I will assume the answer is NO.
    • You would be adviced to add the ClearNvram.efi tool, enable it in your config.plist and run it on the next reboot, see if that helps.
  4. Have you created a new USBMap.kext for your new motherboard.
    • Or are you using the one you created for your previous motherboard?
    • The USBMap.kext contains 22 ports,
    • There is a 15 port limit per USB controller, so you need to reduce the number of ports the kext is activating.
  5. As you have a USBMap.kext why are you using the SSDT-USB-Rest.aml and SSDT-USBX.aml, doesn't the USBMap.kext deal with all the USB issues, such as power etc.
  6. The OC guide for Comet Lake systems doesn't list the SSDT-SBUS-MCHC.aml among the necessary SSDT's, so are you sure you actually need it?
  7. It does list the SSDT-RHUB.aml for use with Asus boards, which you don't have in your /EFI/OC/ACPI folder.
  8. As you have an AMD RX580 dGPU you should be using SSDT-RadeonDeInit.aml, as there is no conversion for the Clover config.plist RadeonDeInit=true option in OpenCore's config. Copy of the SSDT is attached.
  9. Your config.plist lacks an Intel iGPU framebuffer (headless).
    • Have you disabled the IGPU in your Bios?
    • If not you need to look at the DeviceProperties entries in your config and the OC Comet Lake guide and add the necessary headless framebuffer information.
  10. The OC Sanity Checker of your config.plist comes back with a few minor issues, none to worry about -
  11. However, as is common it contains a number of unnecessary 'Place-holder' entries, which can be removed to make the config easier to read and understand.
Probably not the answer you were looking for, but here you go.


    972 bytes · Views: 17
Not open for further replies.