[Seal MT][Caribou]20.04 X59,Black screen appears when installing Ubuntu on AMD 540 graphics card and CML CPU

[Vivi-Tsai]

[Reproduce Steps]
1. Connect the system via 540 graphics card +CML CUP.
2. Clean install Ubuntu 20.04
2. A black screen appears on the system.

[Result]
Expected Result
OS can be installed normally.

[Actual Result]
Clean install Ubuntu 20.04. After "Copying installation logs", the system reboots and the screen goes black. The Ubuntu system does not install successfully.

The reproduce steps :
Insert the U disk -> power on SUT -> error log will appear -> select the hard disk to install OS -> processing of copy files -> auto restart -> Dell logo show up -> error log appears again -> VP on CML +X59 (black screen) / VNP on RKL +X59.

Others info:
VNP on RKL+UMA
VNP on CML+singel 550
VNP on CML +single RX640
VNP on RKL +single 540
VP on CML+UMA
VP on CML+singel 540

[Additional Information]
1. Test Vault ID: adhoc
2. Checkbox test case ID : NA
3. BIOS Version: 0.5.28
4. Image/Manifest: Ubuntu 20.04.1 LTS (fossa-cubone x59)
5. SKU: OptiPlex 5090
6. CPU: CML ES QSRK
7. GPU: singel 540
8. PIMS-27206 / Launchpad:#1906140

Failure rate: 3/3 times

[Vivi-Tsai (vivi-tsai)]

Sorry.....report wrong place

[Daniel van Vugt (vanvugt)]

Is it just the login screen that's black or the whole boot process?

If you can, please boot in recovery mode and then run:

  apport-collect 1908373
  journalctl -b-1 > prevboot.txt

and attach the resulting text file here.

[Vivi-Tsai (vivi-tsai)]

Platform Tag has been added.
Caribou/Buffalo: fossa-cubone-rkl
Seal MT: fossa-seadra-rkl