GPU-Z is a lightweight utility designed to give you all information about your video card and GPU.
Changes in GPU-Z 0.7.0:
Added support for AMD Radeon HD 7990, HD 8550M, HD 7340, HD 7290, HD 8670D
Added support for NVIDIA GeForce GT 740M, 680MX, 675MX, GT218 based 9400 GT
Fixed TMU count for RV620
Fixed voltage monitoring on HD 7790