MSE is too heavy for my PC...

I'd like to install a GOOD anti virus which is also light on the RAM :)
I'v heared about Panda Cloud... Is it anygood?

Im seek of Avira and MSE...

How is it too heavy? You have 4GB of RAM.

Im not talking about the current one Im using.
I got another PC which is pretty old...

ESET comes to mind.

Great! I'll consider that :)
Umm.. What about Panda Cloud?

That'll do the job too, although I prefer resident protection on my systems.

I'v heared Panda is kinda lame but their latest version is great!
Is that true? Also Consider that I have SandBoxie and MalwareBytes :)

The free version is missing some features you won't miss but it will probably nag you to upgrade it. What are the specs of the older PC?

1GB of RAM.
Some pentium 4 CPU
Nvidia GT 6400

Linux OS but Im gonna install XP soon :)

MSE will run on that with no problem as will the other choices.