How do you currently see if the temp is over 75 degrees? Does it log a syslog?
Either you can alert on particular syslogs or SNMP traps. Or you could write a UnDP to do what you want and then alert on it.
First, add this node to SolarWinds as SNMP (I am sure you did this)
Next - run "List Resources" > Hopefully this will bring on hardware for you
Add hardware resource on your node page if you haven't done it already. It is called "Current Hardware Health"
Then, if you are on latest NPM 11.5 AND if you have managed to add hardware as described above - you can adjust thresholds the way you want them for hardware sensor > click on "MANAGE SENSORS" in the "Current Hardware Health" report
You will then need to create alert to alert you if hardware sensor is critical/warning on this device
If your hardware does not show up in SolarWinds - you have the following two options:
Configure UnDP to extract the value of your temperature via OID. You will need to find out what OID is from the MIB or just Google it
Create template based on SNMP to do the same as in option 1. I would prefer this one, because you will then have your temperature graph and you can then easily setup threshold on template level and apply for multiple devices. Below is an example I have: