GUIDE How to Enable AMD Radeon RX 6700, RX 6700 XT, RX 6750, RX 6500 XT and RX 6400

[EliteMacx86]

Hey! Any news on Navi 24 support? Just to know.

Not yet ;(

 

[attia_ahmed]

13700k, z690 gaming x ddr4, rx6750xt, 3x 1080p + 4ktv, getting random freezes for few seconds, mouse is moving, audio is playing, but nothing is clickable, then everything goes back to normal (sometimes colored squares or lines artifacts appear, then it goes away) rx6750xt working fine in other OS windows and linux, my questions: how to solve this freezing issue? a long chat with AI, inspecting tons of logs the conclusion was (screenshot) Q2. is it required to have pre-installed macos? (I can not install the system while nootrx enabled)? i tried installing Tahoe on another machine I5 6600 with WEG and spoofed IGPU then take the installed disk to my main rig but the freezes was even worse

 

[EliteMacx86]

13700k, z690 gaming x ddr4, rx6750xt, 3x 1080p + 4ktv, getting random freezes for few seconds, mouse is moving, audio is playing, but nothing is clickable, then everything goes back to normal (sometimes colored squares or lines artifacts appear, then it goes away) rx6750xt working fine in other OS windows and linux, my questions: how to solve this freezing issue? a long chat with AI, inspecting tons of logs the conclusion was (screenshot) Q2. is it required to have pre-installed macos? (I can not install the system while nootrx enabled)? i tried installing Tahoe on another machine I5 6600 with WEG and spoofed IGPU then take the installed disk to my main rig but the freezes was even worse

Attach your EFI to check.

 

[attia_ahmed]

Below is my EFI download link. Thank you in advance.

Dropbox

www.dropbox.com

Everything else works. Wireless AX210 Working with itlwm Intel BT not working, Audio with VodooHDA, I even managed to make a CSR 4.0 BT Adapter work with BlueToolFixup, SAS HBA, etc The freezing issue is the only problem I can see.

 

[attia_ahmed]

I think I finally fixed the freezing issue I’ve been suffering from since Sequoia. and please correct me if I’m wrong. (XFX Speedster QICK319 Radeon RX 6750XT 12GB GDDR6)

After a lot of testing and log digging, and some AI-assisted log inspection, it turns out the culprit was Resizable BAR (ReBAR).

Here’s what solved it for me:

• BIOS → Resize BAR Support: Disabled
• OpenCore Config → ResizeAppleGpuBars: -1
• OpenCore Config → ResizeGpuBars: -1

Since applying them, the system has been rock-solid — no more random freezes. Let’s hope it stays that way

From what I’ve seen in the logs, when ReBAR is enabled (either in BIOS or through OpenCore), macOS sees an unexpected BAR size, which leads to incorrect VRAM address mapping or invalid port references. During display reinitialization (the “modeset” event — waking the display, switching resolutions, or triggering a GUI redraw), the AMD driver then tries to access VRAM through this invalid range, causing a kernel stall or freeze.

Disabling ReBAR forces legacy 256 MB BAR segmentation, which macOS’s AMD drivers (especially AGDP and AMDRadeonX6000) expect — and stability is restored.

 

[attia_ahmed]

Sadly, the problem persists. While playing DRM video on Prime Video, the system experienced a full GPU hang and freeze. Kernel log shows: IOAccelDisplayPipe (fbindex=0) transaction ... time out, AMDRadeonX6000 channel 34 GFX is hung, and tOS: Exception Address = 0x00000000. Around the same time there are many ModesetCallback / ValidateModeTiming events and repeated transferI2C() !!! Failed I2C transfer for link:0/1/2. System attempted a GPU restart (Trying to restart GPU (AMD Radeon RX 6750 XT)...) but the restart path timed out (Stamp Timeout for KIQ Submission!). Reproduced with ReBAR enabled; disabling ReBAR (BIOS + OpenCore ResizeGpuBars/ResizeAppleGpuBars = -1) removed the freezes in my testing. Attached: contiguous kernel log ±60s around the freeze.

 

[EliteMacx86]

Below is my EFI download link. Thank you in advance.

Dropbox

www.dropbox.com

Everything else works. Wireless AX210 Working with itlwm Intel BT not working, Audio with VodooHDA, I even managed to make a CSR 4.0 BT Adapter work with BlueToolFixup, SAS HBA, etc The freezing issue is the only problem I can see.

Your EFI is not as per the guide. You don't need SSDT-PMC.aml.

Why are you injecting SSDT-SBUS-MCHC and then also renaming MC to MCHC?
Why are you using CPUFriendDataProvider and then also injecting vectors via the SSDT-CPUF?
Your board has only Realtek NIC. Then why are you injecting AppleIGB?

What HBA card are you using?

You should consider enabling VT-d.

 

[attia_ahmed]

Your EFI is not as per the guide. You don't need SSDT-PMC.aml.

Why are you injecting SSDT-SBUS-MCHC and then also renaming MC to MCHC?
Why are you using CPUFriendDataProvider and then also injecting vectors via the SSDT-CPUF?
Your board has only Realtek NIC. Then why are you injecting AppleIGB?

What HBA card are you using?

You should consider enabling VT-d.

Thanks for reviewing my EFI — I really appreciate your time, effort, and detailed feedback!
I’ve gone through and cleaned up the setup based on your recommendations:

• Removed SSDT-PMC.aml — According to Dortania’s “SSDTs the Easy Way” guide, it’s intended for Intel true 300+ series, which I mistakenly interpreted as 300 and above.
• Kept SSDT-SBUS-MCHC, but removed the MC → MCHC rename patch.
• Removed SSDT-CPUF.aml, since CPUFriendDataProvider already injects the correct vectors. (That was an AI suggestion earlier — but yes, it’s always better to talk to humans ).
• Networking setup:
  • Realtek RTL8125B 2.5 GbE — directly linked to my power-hungry TrueNAS system via a matching card for maximum throughput.
  • Intel i210 (IGB) — connected to my home network (1 GbE switch/router).
  • I rarely use WIFI, so I replaced the Intel AX210 with the HBA.
• My HBA: HP LSI SAS 9217-4i4e — confirmed working under Sequoia (13700K + Z690 & i5-6600 + H170M) with AstekFusion2 kexts (not yet tested on Tahoe).
• VT-d Enabled: I virtualize OpenMediaVault to share a small internal 4×3 TB storage pool across OSes (serves as an exFAT alternative, reduces the TrueNAS system power consumption, rarely used now).

Unfortunately, the random GPU freezes are still happening — mouse and audio remain active, but the UI locks up for several seconds, sometimes showing colored lines or square artifacts before recovering.
I’ve attached a log screenshot captured during one of the freezes for reference.

At this point, I have two questions before moving forward:

1. Should I spoof the RX 6750 XT to RX 6600 XT following the “Spoofing Graphics on macOS” guide?
2. Is a clean installation required with NootRX disabled (then enabling it afterward), or should I install macOS first on a more compatible setup — e.g. my i5-6600 + H170M — as mentioned in the guide (“Pre-installed macOS Big Sur 11.x or later”)?

Thanks again for all your support and insights — this community really helps bridge the gap between theory and real-world experience!