So, dedicated server? Why, can you explain what will you run on it, how many server/services?
Dedicated servers are not cheap but are the best solution if you know how to manage it. Its not really easy to install and maintain servers so if you're not that tech savvy and if you want to run just one PR server maybe solution like Alpha Networks is offering is right thing for you.
Game Servers | Alpha-Networks | Low Latency Game Servers
Like I said it all depends on what will you be runnig on a dedicated server if you really want one. Mine is i5 4x 2.66+ GHz, 16GB RAM, 2TB HDD, 100Mb up/down link. And I run 2-3 PR servers, Arma2 Co server, TS3 server/s and there will be more possibly in future. Its not on Windows its on linux without GUI interface so it looks like this.
And all setup goes like this. Sure this is linux but I find it
better than any Windows OS, especially without GUI cause it take less resources, its faster, no viruses and highly configurable, thus not easy to setup and maintain. Moderate to high knowledge needed.