For 7.0 issue exist only for Graph, but starting from 7.4 issue impacts Graphprototype as well.

Steps to reproduce:

1. Create Graph or Graph prototype
2. Enter max allowed 'Height' 65535, for 8.0 it should be 4500
3. Save
4. Go to: Monitoring->Hosts and click on 'Graphs' for the host

Result:
Instead of Graph observe error:

Page received incorrect data
Incorrect value "65536" for "height" field: must be between 20 and 65535.

Expected:
Graph is shown successfully.