Glitches when spoofing HD 530 as HD 630

Hi, I am running macOS Sonoma 14.1.2 (23B92) on my Skylake desktop build. I only have a single ultrawide display connected to my dGPU.

• CPU: Intel i7-6700 CPU @ 3.40GHz
• iGPU: Intel HD 530
• GPU: AMD RX 580
• Board: Gigabyte H170M-D3H
• OC: 0.9.6
• Lilu: 1.6.7
• WEG: 1.6.6

In order to run Sonoma I changed my SMBios from iMac17,1 to iMac19,1.

I also spoofed my iGPU HD 530 as HD 630 to get hardware acceleration when encoding videos.

While the new OS mostly runs pretty well on this unsupported hardware I get glitches in some apps. So far I noticed:

• Red backgrounds flashing in Safari when closing tabs (only briefly visible)
• Garbled animated covers in Music.app
• Color tint and split screen when using the new video screeensavers/wallpapers.

https://preview.redd.it/rsssobw9m35c1.png?width=4032&format=png&auto=webp&s=6df7e7bbb42f02753616c99e93e34cd379a0d99a

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https://preview.redd.it/iw8a45hsm35c1.png?width=1048&format=png&auto=webp&s=ac54e486db11ca9ade905b8cd8ba21a119a88f15

https://preview.redd.it/fd56nj1yo35c1.png?width=444&format=png&auto=webp&s=23f77287389dee47984fae1b8955d107ff50a548

I tried to inject AAPL,GfxYTile with the value 01000000 but I didn't notice any changes. When I boot with -wegnoigpu to disable the iGPU the glitches are gone but so is hardware acceleration.

I also have a thread on the discord with lots of additional information: https://discord.com/channels/186648463541272576/1181166961212784770

Anybody have an idea how to get rid of these glitches while keeping hardware acceleration enabled. I am really liking some of the features of Sonoma and it fixed some bugs in apps that I use daily.