Should I get a server with more RAM or Faster Processor?
 

What would be better to get:

4GB instead of 2GB of RAM with a Core2Duo E8400 3.0GHz processor

or

Core2Quad Q9450 2.67GHz with 2GB of RAM

Thanks.

Get the ram, as you forum hasnt yet broke the 1 million post mark, the ram will benefit you in the growth process, cpu usage can always be cut down later with simple stuff like disabling modules server side, turning off programs not needed but running etc....

I'd say whichever is your limiting factor. If you don't need the extra ram the faster processor should give the better benefit (provided web server is configured properly to use all the cpu's).

More RAM will probably benefit you more - providing you configure your apache and mysql to make use of it.

On the other hand, if its a dedicated server you are renting; it'll be easier to add more ram in the future whereas processors usually require a whole new server.

As SQL is RAM & DiskI/O resource heavy, the adv goes to the RAM upgrade, as Crapache (Get rid of Apache, the best thing you can do!) is as waste of resources in itself, CPU would be more beneficial, if your forum is sucking up huge amounts of CPU% usage on the server in TOP, then you have other issues you need to address.

I would go with more RAM ATM as well

So with RAM.

And stick with Apache2 if you need extensions like mod_geoip, mod_rewrite, etc. Many people will advise you to drop Apache and go with a lightweight web server. I do not recommend you do this without considering the extensions you need. If you don't need any extensions like mod_geoip, etc then you can go for something more lightweight. However, if you are a web publisher, your will find great benefit in running things like mod_geoip, mod_rewrite, etc.