The Problem: 

I have a Cisco Switch 3750e. The Syst Led is solid green after reboot. It was working fine untill it was rebooted.

The Cause:

It is the hardware, the memory component.

http://www.cisco.com/c/en/us/about/supplier-sustainability/memory.html

http://www.cisco.com/c/en/us/support/docs/field-notices/637/fn63744.html

A temporary fix?

Open the case and remove the heat sink.

Use a hot gun to heat up the memory components for about 5-10 mins. This will “reflow” the solder connections on the chips.

Here is more info if you would like to read.

Heat gun GPU reflow fixes laptop

Good luck!