Short answer - you are going to have to ask Dell.
Longer answer - Inspiron 5675 is sold in either Bristol Ridge A-Series or Ryzen Series models. Dell uses slightly different motherboards for these. The differences appear to be more SATA and USB3 ports and an extra PCIe x16 slot for the Ryzen board, with the layout of all other components the same.
The real question is BIOS support. We have heard that there is a BIOS capacity issue that causes there to be insufficient space for both Bristol Ridge and Ryzen CPU support. Some board manufacturers dropped support for Bristol Ridge in favor of support for more Ryzen models. This may be why Dell has 2 motherboards listed in the specifications - possibly one for Bristol Ridge and one for Ryzen. If that is the case, then you may not be able to upgrade. Alternatively, maybe the Bristol Ridge motherboard has fewer features merely as a cost savings measure, in which case upgrade is possible. If so, then according to Dell, you can upgrade to as much as a first generation Ryzen 7 1700X. So - ask Dell.
