Having a light yet efficient Antivirus goes hand-in-hand with owning a high performance computer.
Windows 10 ships by default with Windows Defender which is a FREE Antivirus, and while it is good in terms of protection it is one of the most resource heavy Antivirus solutions out there and will cause a huge drain on the system, particularly noticeable when installing or running applications. You can see the latest AV Comparatives chart here (the lower it is on the graph, the lighter it is on your system).*
We highly recommend ESET NOD32 Antivirus as it has been the preferred choice for gamers and performance enthusiasts for 2 decades! It has a very powerful file scanner, HTTP scanner (to block malicious connections and downloads), and contains no bloatware (i.e. system optimizer, toolbars, search engine, etc.) and does not interfere with any software or Windows updates unlike other antivirus software.
*While you may notice that there are a few lighter AVs, our performance experts have extensively tested them all and we do not recommend them either because they give a lot of FPs (False Positives), contain toolbars and potentially unwanted apps such as a VPN or system optimizers which usually do more harm than good, or simply have adverse effects on the system in terms of compatibility with certain apps.