iMac Quadro P3200 rom:
- Enables the internal display.
- Enables GOP boot screen using Opencore.
- Brightness control and sleep/wake work.
- Max GPU clock raised from 1542 to 1594 MHz.
- Max Memory clock raised from 3500 MHz to 4000 MHz.
- Max TDP raised from 80 to 115W.
- Power Limit (%) slider unlocked in Afterburner, to decrease the Max TDP if desired.
- Temperature throttle limits slightly increased.
- NVGI header added for ease of Windows driver install
- External display is enabled and tested on the mini DP closest to USB ports.
Many thanks to
@jay508 for help and long time spent testing this card and vbios.
Windows 10 will automatically recognize card and install Nvidia drivers. You can use
NVCleanstall if you wish to update to the latest GeForce drivers.
To enable brightness control on Windows you need to
manually add the same registry entries as with other Nvidia cards.
Works on MacOS High Sierra with Web Drivers.
GPU clock can be locked to a specific value using the voltage-frequency curve in Afterburner. The curve itself can't be edited (no undervolting possible).
3 pipe heatsink and install with good thermal paste is a must.
The card we tested (board DAXW3UB5CD0 REV D) needed to apply the
smbus isolation trick to work properly on the iMac 12,2. There is a smbus collision that makes the card work at ~50% power if SMB_DAT track is not isolated from the mxm connector. This hack may not be needed for other models of iMac which use different smbus addresses, or other different card pcb revisions..
See picture below for how to isolate smbus track,
@jay508 tested nail varnish, cyanoacrylate glue and uv curated solder mask to cover track, first two were removed after some insertions/removal of card, but for light use it should be enough.
You must use a hardware programmer to flash this rom on the eeprom chip at
1.8V (nvflash will not work, as digital signature is invalid). Also take into account most cards come without eeprom chip onboard, you have to use a nvflash compatible 4M-bit 1.8v eeprom chip like W25Q40EW / W25Q40EWNIG for the bios (some sellers may offer to solder it for you).
Card performance is great, it performs like an overclocked P4000 at half the price (4500 gpu score on Time Spy).
Display tables changes based on
@Santa's Little Helper work for the P3000/P4000 cards.
**UPDATE**
2022-11-24 MacOS brightness issue fixed.
