FRAPS
- displays FPS in-game, records in-game video etc.
http://www.fraps.com/download.php

HWMonitor
- HWMonitor is a hardware monitoring program that reads PC systems main health sensors : voltages, temperatures, fans speed.
http://www.cpuid.com/softwares/hwmonitor.html

MSI AfterBurner
- GPU monitoring and overclocking tool
http://event.msi.com/vga/afterburner/

RadeonPro
- Setting game specific 3d profiles for Radeon cards
http://www.radeonpro.info/en-US/

GPU-Z
- GPU info tool
http://www.techpowerup.com/gpuz/

CPU-Z
- CPU info tool
http://www.cpuid.com/softwares/cpu-z.html

GPU Caps Viewer
- another GPU info tool
http://www.ozone3d.net/gpu_caps_viewer/

TeraCopy *highly recommended
- speeds up file transfers
http://www.codesector.com/teracopy.php

CCleaner
- cleans the junk out of your hdd
http://www.piriform.com/ccleaner

GIGATweaker
- GIGATweaker is a free powerful and compact tool
that allows you to optimize and tweak your Windows 7
http://7room.net/gigatweaker/

avast!
- best AV out there
http://www.avast.com/en-eu/free-antivirus-download

Malwarebytes Anti-Malware
- best malware remover
http://www.malwarebytes.org/products/malwarebytes_free