Big Sur on socket 775 with Clover: booted and actually quite usable
As you can see here is my socket 775 machine running big sur beta 1, it has been quite a journey, it took me 3 day to accomplish this, the most difficoult thing has been modifing the Big Sur system partition to allow boot on suck an old cpu. I just used my knowloadge to achieve this in vanilla without any giudes, i need an orignal mac to perform os installtion and preparation for boot on the old hardware.
I won't make any guide because it's just too much work but i leave you some some knowladge about this thing.
Parts I used:
-Intel core 2 duo E8400 (every socket 775 cpu supporting sse4.1 is ok)
-Asus p5q3 deluxe (i tried this EFI folder with catalina o a bunch of socket 775 motherboards and it worked on all of them, so it whould work just fine with big sur too on all of those mobos)
-GT 710 (almost every kepler-based nvidia card is ok, but not amd cards since the amd drivers on this version requires a more recent cpu and UEFI booting)
-6 GB (3x2gb) Corsair XMS3 1333 mhz (my mobo is compatible with just old ram)
-intel stock cooler (on this socket a nice old beefy intel stock coller is more than enought if you don't overclock it, especially with core 2 duo cpus, and i am on the budget for this testbench so i just used some cheap stuff i had layng around)
-120gb Sata ssd (don't use hard disks or it will be painfully slow)
-Terratec audron 7.1 space sound card
-Creative Sound blaster audigy 2 zs platinum pro
-Spare old power supply just to put the testbench together (don't reccomended of course, always use good power supplys)
Works everithng except for:
-USB (apple remooved support for this older usb controllers which used to work on catalina so you need a dedicated pcie usb card to have working usb ports)
-on board audio (mine is just broken)
-Sleep/wake
-Combo p/s 2 port (never worked on mac)
Things that amazingly still works:
-On board IDE (using a 64 bit version of SuperVIAATA.kext)
-On board PCI slots
-On board marvell ethernet controllers (using some old 64 bit kexts)
-On board firewire (kindof it is just recognized but i can't test it and most likely it isn't working)
-A bunch of other old PCI cards using some old kexts compiled as 64bits, including the old sound blaster audigy i mentioned.
-On board COM port
-All the on board sata ports (using an injector kext)
Things that i didn't need to use:
-OcQuircks (because this PC uses legacy booting all the memory is free to use and so all i needed is the patched clover binary with the kernel patches in the config file)
Things i had to use:
-An original mac to install the os and then modify the system partition to delete the telemetry plugin located in /System/Library/UserEventPlugins (which is necessary to allow booting on systems without a cpu supporting SSE4.2)
-FakeSMC (i can't boot with VirtualSMC)
-imac14,2 smbios with the -no_compat_check boot arg (since all the other supported smbioses gave me a black screen at boot with my nvidia card)
-Plenty of experience making vanilla hackintoshes and socket 775 hackintoshes
I leave also there a screenshot as proof (i don't care about the serial number) and a cinebench R20 score of this ancied CPU done on Big Sur.
