XPS 8500 mods & power temp monitoring

Wondering how I could monitor power usage and maybe temperature with software.

XPS 8500 stock was:
Win 8
8GB
2TB drive
AMD 7570
DVD-RW

Added:
2TB WD Black in 5.25 bay
1TB WD Blue under 2TB Dell drive.
replaced video with EVGA GTX 660 with UEFI bios update
replace DVD-RW with Bluray
+4GB

Everything is working great so far.