Windows 7 - Skype video quality

I've noticed this recently. I've tried posting in the Skype community with no luck.

My computer is as follows:
E6750 OC'd to 2.933
4 GB RAM PC-6400
eVGA GTX 460 SE 1GB

Basically, I use the "Nightly" browser from Firefox, which is a 64-bit version of Firefox. With Resource Monitor, I'm noticing that I'm consistently hitting over the 3.3 GB RAM (can't remember if the mark is 3.3, 3.2 or 3.1) mark for 32-bits. I usually have a lot of applications simultaneously running on my computer. Then, when I run Skype, I notice that my video call quality is pretty bad. Even closing "Nightly" doesn't really help too much. Resource Monitor still says that the memory that was used is still not 'free' but rather in 'standby'. Does this make any difference?

Why is this? Is it because Skype is a 32-bit application and cannot access memory within the first 3.3 GB? Forgive me, I'm a 'noob'' here. Are there any 'tweaks' I can do to my computer to fix this problem?

Has this always been the case?

When you say "video call," do you mean both the audio and video quality? The components you've touched on are probably all fine, working as they should and doing their best for your programs to be top notch fast and capable. These components, however, can only do so much-- the main things you should look at are your speakers/audio card, microphone, and webcam.

Standby is a feature in windows 7 which handles RAM More efficiently

What is your Internet speed? Does this happen on all Video calls with all your contacts?

Speedtest.net - The Global Broadband Speed Test

Your specs say win 7 64 so what 3.3 gig mark?. Nightly (IM running it too) does have a memory leak but that isnt affecting your skype calls.

Is this a recent development?

Please take a snip of tsk manager process tab sorted from memory.