Upgrading your Portal's CPU and RAM typically does not require any post-configuration.
A few things to consider to help narrow down the issue:
- Does this machine host only Portal for ArcGIS, or are other ArcGIS Enterprise components (like ArcGIS Server or Data Store) also installed?
- Is the issue specific to the Portal Map Viewer, or do the same layers fail to load in other apps like Experience Builder or ArcGIS Online Map Viewer?
- Do Portal, Server, Datastore logs reveal anything?
What kind of layers have you tested and where is their source data located? e.g.
- Hosted feature layers from the relational data store?
- Referenced feature services from an enterprise geodatabase?
- Hosted imagery layers from the raster store?
- etc
Answering these questions may help pinpoint whether it's a display/rendering issue, a service/data access issue, or something else.
