5 Boxing Help please.

Im having trouble running them. Im ok with a little lag but there seems to be a bottleneck somewhere.
All my clients are at the bare minimum settings.

In ISboxer they are set at 30/20 FPS with round robin(Dedicated 1st core)

My specs are
i5-2500k @ 4.5ghz
8gb ram @ 1600
AMD 6970 2gb card
SSD

My GPU stays 80-90% load
CPU 100% (Happens a lot. Especially when loading)
Ram is at 7gb used but im not sure if it wants more.
I could buy another 8gb of ram but would that help my cpu load if it needs more?
I don't want to spend 350$ on an i7

[MiRai]

If you already know what the load is on your hardware, then you should start turning down your in-game settings to see which affects it the most. This includes, but is not limited to, background client FPS and possibly having to use the Low Quality Renderer. As an example, if your cut your background FPS down to 10 FPS for each client, that's saving you literally 40FPS of load on your hardware. I wouldn't recommend any lower than 10, though.

RIFT's game engine has been known as a resource hog while multiboxing since its inception.

Thanks for the reply. I have he game at minimum and i have tried setting fps to 10 on my back ones. It helps my mains fps some but the CPU usage is still high.