Originally Posted by Scott-Mc

You can run with slightly high load (a load of 4 isn't really a big deal) without much difficulty it would ultimately depend on how slow your website is loading.

With the amount of processors most new systems have load isn't really a good way to monitor something, providing it loads quickly then you can assume it's fine.

It's going to have to be extremely slow for it to cause some serious effects to half your traffic (That is assuming that is the problem and you just havn't been dropped from the SE/link that was giving you most of the traffic).