Is this normal? please help

Just wondering if this is normal. 3 threads open and I use up 99% of CPU.

And also, i realized that GSA seems to only use up to 200MB memory only. I am a little surprised, because i see most of you here recommend 2-3GB ram. 

whats your computers ram?

are you running other programs? that could be taking up the rest of your memory. Open up your task manager go to processes, sort by CPU and it will show you what is taking up the memory. It could be another program you might think it closed but it is actually open.

I am running it on a VM with 3GB ram assigned to it. No other programs running that same VM

For the CPU, its share among the entire computer, but i arent running anything CPU-consuming on other VM neither. 

I've noticed something similar. It'll display CPU 99% within GSA SER, but on the servers task manager, the CPU will only be about 30%

Yes the CPU load is not as accurate as it is just monitoring the current CPU it is executed on. If you have 99% CPU load and 2 CPUs, it could as well be 50% load maximum only. I try to optimize this but it is no priority right now.

So 99% shows CPU consuming for the 'entire' computer right - which means, in general, i might be overloading my comp and its time for a new one?

I agree with Doubleup and Sven, it's not high priority.  Generally I'm using 25% CPU when GSA reports 99%.