Hard drive requirements ,is disc allocation still necessary in HDX

[Weird Audio]

My system has not been giving me it best as of late.
Im thinking should I be using more drives for my sessions because HDX can easily handle what is there but still something is lagging.

Here is my session over view
32bit / 96k
1024 samples
14 processors
95 % usage limit
128 voices
maximum delay comp
6GB disc cache . (20gig mac 8 core)
Level 2 plug in buffer
unchecked optimized streaming PI content


85 total channels
64 audio tracks
48 mono audio tracks
16 stereo audio tracks
13 aux .
7 busses
1 master
_________________
115 total PI,s
31 DSP PI,s
84 native PI,s

75 / 80 % cpu in use
115 voices


Whats your take on this .
Is this normal or should I be getting more out of this configuration
Mac 5.1 lion 20gb 2.4GHz 8 core . Two 1 TB harddrives , system and audio only . HDX 1

NO HACKED PI,s AT ALL just legit owned or demo,d PI,s no "borrowed" anything .

I am wondering if I need more audio drives or even ram .

Loading PT from the internal system and audio drive takes about 2 minutes and 30 seconds for all the controls to be fully responsive. .