Toshiba Satellite A505-S6033 Performance and RAM limits

Lately my A505 is getting a little slow... Not much help from cleaning up system... installed ubuntu and runs great... anyhow I noticed I was low on RAM nearly all the time so I went to Best Buy to get upgrade - they sold me PNY 2x4GB DDR3 PC3-10666 which says its compatible with 1333 and 1066 Mhz. The PNY number is MN8192KD3-1333-AP.

Upon installing the system appears to recognize that there is not 8GB available - but windows shows 8GB installed (2.94GB usable) in the computer management window.

This prompted me to double check to see that the new modules were seated properly - they were. I installed the old modules - 2x2GB and those worked fine... I reinstalled each 4GB one by one in both slots - laptop picked up on the 4GB no problem in each slot separately.

I reinstalled both 4GB modules. I ran the msdiag memory test - everything passed fine.

It still shows only 2.94 usable. Not sure about this one...

I then checked bios setting - I did not see anything obvious that needed to be adjusted.

I then rebooted and looked at Windows resource monitor which shows all 8GB broken down as follows:
5186 MB Hardware Reserved
2103 MB In Use
45 MB Modified
856 MB Standby
1MB Free


These numbers fluctuate depending on use - but 5GB set for hardware reserved makes me wonder what is going on...

I then hopped on the Toshiba support page - downloaded their bios update tool - installed and ran it - I am already using the 1.4 version which is their latest released version.

I then checked the Toshiba Accessories search for memory upgrades - it suggests using Kingston or Toshiba PC3L 1600Mhz modules and offers either 2 4GB sticks or 1 8GB stick...

I am wondering the following?:

1) Why does my laptop show 5GB reserved for hardware with the current PNY memory
2) Will this be the same if I get the more expensive 2x4GB modules from Toshiba that are 1600 Mhz?
3) Why does Toshiba recommend the 1600Mhz when I have read elsewhere on here that the HM55 chipset (I think this has) and the i7-720QM processor that this has in it will not handle the 1600Mhz speed - or will it with the mobo that Toshibal built in the A505-6033?

4) What do you all recommend that I do for increasing ram to at least 8GB?

5) Are there any options to upgrade chipset controls or other means to expand beyond 8GB of physical ram? I would like to have 2 8GB sticks for 16GB total... I do a lot of number crunching and algorithmic data analysis on the fly and I run out of memory all the time... so it starts using swap and sometimes the swap can not keep up so it errors out... no problems with same data set on larger server banks with hundreds of gigs of ram... anyhow - I would like to improve the performance of this laptop and increase its ram. It has been a good laptop overall - I have to be careful to keep it clean and I have had to open it a couple times to blow out dust bunnies on the headsinks which improved its overheating issues - only thing I had to replace was the battery and I got a larger one that props the back of the laptop up a little and improved the heat issues even more. Games as well as business functions all work well on this machine - overall a good buy and has lasted me for 3 years - I am hoping to squeeze another year out of it.

-TheSailor