Need to add RAM if possible: Compatibility and is it possible?

System Specs are fully updated.

Link to PDF of System Specs from specific model from Toshiba.com.
satellite_L645D-S4056.pdf


I need to add RAM. It currently has 4GB, but it isn't sufficient. I have to use VMWare workstation, Microsoft Office, Google Chrome, and possibly Microsoft Project, and other high resource software.

It says both slots are occupied (I am guessing 2GB per slot).

How difficult is it to replace? Is it worth it?

Average cost? Can you recommend one? Ideally, 6GB-8GB is desirable. I don't have much to spend.

I am an Information Systems student (for tech knowledge).

I had the same issue. Access to the System Board (which was defective and Toshiba had to replace it) requires pulling out the processor. I couldn't find the manual either :/

Manufacturer AMD Corp.
Model Guam (Socket S1G4)
Version PSK0QU-01200D
Chipset Vendor AMD
Chipset Model 785GX
Chipset Revision 00
Southbridge Vendor AMD
Southbridge Model SB850
Southbridge Revision 40
System Temperature 70 °C

If I can only afford to buy 1 of these, is it advisable to upgrade to 6GB of RAM (2GB OEM in one Slot, 4GB in another)?
OEM was Samsung, New would be PNY.

The Laptop is about 5 years old. What are you guy's thoughts. Should I bite the bullet and stay on this PC and is 6GB of RAM even sufficient or compatible? or wait until around January-Feb of 2016 when things get smoothed out and hardware advances are made 6 months after RTM of Windows 10?

Either is an option at this point.