I have written previously about Building a Workstation for SQL Server 2012 Development and Testing and Building a Larger Capacity SQL Server 2012 Workstation. In those posts, I talked about the fact that it becomes increasingly expensive to build a system from parts as you move beyond mainstream desktop systems based on an Intel Core i7-3770 or i7-3770K processor.
If you actually need more than 32GB of RAM or more than four physical processor cores, you will have to move up to a single-socket, Sandy Bridge-E, Socket 2011 system, which maxes out at 64GB of RAM and six physical processor cores, at a considerably higher cost. The next step up is moving to a single-socket, Sandy Bridge-EP system with one Intel Xeon E5-1600 series or E5-2600 series processor with up to eight physical processor cores and 128GB of RAM.
Finally, you can buy the components for a dual-socket, Socket 2011 system with two Intel Xeon E5-2600 series Sandy Bridge-EP processors to build a much more powerful and expensive system with up to 16 physical processor cores and 256GB of RAM. By the time you do this, you may end up spending so much money that you would be much better off buying a refurbished, actual server from someplace like the Dell Outlet.
Depending on what you are planning on doing with your server, you can choose a Tower server, a Rack server, or even a Blade server. Depending on your infrastructure, you are probably more likely to be looking at a tower server or a rack server.
One tactic I like to use when I am searching for a server on the Dell Outlet is to focus on the installed processors in the server. You are very unlikely to ever upgrade the processors in a server after you buy it since processor upgrade kits are usually quite expensive. That means you should focus on the processors and not worry as much about the amount of RAM. Getting more RAM later is easy and inexpensive.
Storage is a little trickier. Sometimes you can find outlet servers that have a lot of big, fast internal drives that are bargains. You may also be better off to think about buying a number Intel DC S3700 SSDs along with compatible 2.5” drive carriers from someplace like Amazon (since Dell does not seem to like selling empty drive carriers very much). You should be on the lookout for systems that have decent RAID controllers in them, since they are relatively expensive to buy later.
As you get ready to buy a server from the Dell Outlet, you want to make sure you have the necessary means of payment ready to go as soon as you find the system you want, since their available inventory is constantly changing. If your organization has a lot of bureaucratic overhead, it may take too long for you to get the necessary approvals before that system you were interested in is no longer available.