Weird VST Performance Issue vs Windows Resource Pls Help

I Have noticed a strange issue where VST Performance average load and real time peaks are maxing out but at the same time Windows is telling me that my CPU usage is only at 50%. My RAM Physical Memory is being used at around 80-88%. Buffer: 256. Asio guard on, Steinberg Powersaving mode on,

I currently have 12 Gig DDR3 Ram with room to expand to 24 gig. My processor is a first generation Core I-7 960 @3.2 Ghz Socket LGA1366 8MB Cache.

When I first noticed the VST Performance average load and real time peak Maxing out I assumed it was caused by my processor overloading but now I am not sure as Windows is informing me it is only at 50% use?

I am running Cubase Pro 8, 64 bit with only 64 bit plugins. I am looking at upgrading RAM & or Processor if needs be so that I can solve this problem that is affecting my workflow.

I have uploaded some screen shots, it would be great if someone could help me to figure out what is causing the issue?
Another thing that seems to be happening is a massive spike when I open the edit window. This is strange, I’ve never noticed this behaviour in previous versions of Cubase.

Please Help,

Case - Cooler Master HAF X,
Motherboard: Asus Sabertooth x58,
Processor: Intel Core i7 960 @ 3.2 Ghz LGA 1366,
Sound Card: focusrite saffire (Fire Wire),
C: Drive with Windows installed - KINGSTON SV300S37A240G ATA,
D: Drive (Hard Drive with most data) SAMSUNG HD204UI ATA,
Graphics card - Sapphire HD5450 DDR3 PCI-E HDMI/DVI-I/VGA,
Ram 12 Gig DDR3 (Corsair 3x 4Gig Vengeance)

Please help