If the memory was the limiting factor (bottleneck), it would stop your CPU &/or GPU from reaching max load.
100% usage isn't a concern, necessarily - just means the CPU is being fully utilized.
When the CPU is at 100%, what is your GPU utilization looking like? If it's 90%+, you've got a pretty well balanced system.
Are you monitoring RAM usage? If so, what does it look like under a typical gaming load?
yeah i meant quantity because some games say it need min 8 gigs and my ram usage is always almost maxed. cpu and gpu mainly are 100/90 or 90/100. For AAA games my cpu does not have problems but for online games sometimes the fps drops for a second and goes up very often. i thought maybe the ram was a problem.