Well here's the thing, if you are running at least a VPS (you should) you'll find out that the default config for everything (php/mysql/apache/nginx) isn't really what you are after. Especially the default mysql config on most of system is a mess thus the performance of the database isn't really great but there's room for improvements.
I don't know your current configuration to tell you if you need better hardware or not, but the above holds true whatever hardware you have.