Primary Components - Waterblocks
A primary component is something that physically sits on something in your PC. This would include things like Waterblocks, Radiators, Reservoirs and Pumps. I call these primary components because they are core to making your system work and every system will have them.
Picking a waterblock used to be a very involved process involving months of research coupled with cross checking user evaluations and sourcing where to buy. Some waterblocks were sold by individuals while others might be from a larger manufacturer like Danger Den or Swiftech. Thing was every block had completely different performance characteristics depending on the style and may change depending on what CPU it was installed on.
Things have gotten simpler as the technology has matured. Most CPU waterblocks are built on a microfin or micropin construction meaning that performance is virtually identical across the major brands. In fact I have noticed some CPU blocks have been continually offered for over 8 years without a revision leading us to believe they are either “that” good or nobody cares about innovation anymore.
My Suggestion: Process of elimination
First look for a waterblock that fits your processor platform. Next eliminate the blocks that are out of your budget. (read: silver has awesome thermal properties but kinda expensive) Lastly pick one that you think looks good and/or matches the theme you are planning for your build.
Back in the old days everything was universal. CPU waterblocks would have different block tops to fit different processors but the coldplate (the metal part touching the chip) was usually the same. Modern video card waterblocks are designed to be full coverage and are machined to fit only a single type of video card. For instance, if you have an EVGA Classified card you will need a waterblock that is specifically designed for that version of the Classified card. Likewise if your video card is based on a reference PCB there might be a multitude of options available.
My Suggestion: Consider the GPU as an optional waterblock for your loop.
First look to see if a block exists for your video card. Keep in mind that manufacturing costs usually eliminate anything that isn’t considered to be top of the line. Next if a block exists eliminate blocks that are out of your budget and find something that looks good and/or matches your theme.
Cooling performance can vary depending on manufacturer so keep that in mind when making a purchase.