Can I use both 2 slot RAM of my motherboard?

No, they are only there for shits and giggles.

Yes. Be sure and use the same type of ram that it has

in it already. If your system is 32-bit it will real 4 GB but

will only use 3.25 GB of the 4 rams.

If your system is 64-bit you could put 2x4 sticks ram in it

For a total of 8 GB.

Yes. Just make sure you know what types of memory the motherboard and processor supports before buying the 2nd stick of RAM.

Yes you may. Just remember to check the type of ram it supports before going out to get one.

Yes. The motherboard support 8GB max so you could potentially add two 4GB sticks. Of course you need a 64bit OS to utilize it.

Yup, that's what it's for. Just make sure to get the same kind for both slots, and that your computer is compatible with them. (If you don't want to bother with that just get the same type of ram you already have)

sure you could, yet i opt to recommend conserving your 40 GB difficult force and positioned your domicile windows on it and upload the GB difficult force and use it for storage purely, so if your workstation crashes you purely lose the domicile windows records or something you place on the 40 GB difficult force with domicile windows (classes and so on...). additionally positioned one million GB ram in each and each slot totaling 2 GB ram. i'm hoping this enables you.

YES. Or you could replace both of the cards with larger ones, just make sure you get the right DDR

Goddamn you're stupid