There are a handful of programs based on the old Rivatuner which can display a lot of hardware info in an onscreen display over top of your game
the two I use are MSI afterburner and EVGA Precision http://event.msi.com/vga/afterburner/download.htm
afterburner is ever so slightly less annoying since you do not need to create an account to download it.
in the options there is a monitoring tab, and with each metric you can check a box for "show in on screen display"
there is a deeper options menu in that same tab that lets you change the size, position, and color of this display.
try it out and see if its what you are looking for. I run it all the time since I have a shoddily rigged up liquid cooling system and I want to always keep an eye on my GPU and CPU temps in case the system goes bust.
these only will work in 3d applications, so you will have to rely on task manager outside of games. the advantage of these is that you can run a game fullscreen and still see the data.
<message edited by Baffles on Saturday, March 16, 2013 8:40 AM>