2X more RAM-system recources still low

I was having trouble staying online and was told that I probably was getting knocked offline because my system resources were dropping below 75%. That seemed like a good possibility to me because I only had 64mb of RAM and was consistently having to reboot my system because my resourses were dropping down as low as 50%. (It didn’t seem to matter if I closed all the programs or not – they still stayed low.) So, I upgraded to 160mb. So – can anyone tell me why my resources are still dropping down to as low as 60% (rare) -but consistently as low as 70%? It seems like there should have been a much bigger difference the upgrade.