Issue #446 has been updated by Michał Żygowski.
If there are 4 expansion slots, that means you have a DT or MT variant. To support the MT/DT you should at least add an overridetree.cb file, like how I have done it for Precision T1650: https://github.com/coreboot/coreboot/blob/master/src/mainboard/dell/snb_ivb_... Basically the overridetree.cb will be the same for OptiPlex MT/DT (because the Precision and OptiPlex MT/DT board is exactly the same, just a different chipset), you would have to change the subsystem ID only for OptiPlex MT/DT if needed. That will enable the rest of the expansion slots besides the x16 ports.
---------------------------------------- Bug #446: Optiplex 9010 No Post https://ticket.coreboot.org/issues/446#change-1342
* Author: Aaron Burton * Status: New * Priority: Normal * Target version: 4.19 * Start date: 2023-01-09 ---------------------------------------- Working with an Optiplex 9010 SFF, configured and built coreboot as usual against the Optiplex 9010 SFF platform in menuconfig. Left every other setting alone in terms of configuration. Included EC firmware, ME, GBE, IFD blobs from stock firmware into my build. Turns on with fans at normal speed (not full blast), but no keyboard illumination or display output. Using SeaBIOS 1.16.1. Any suggestions as to what may be going on? Thanks.