Nowhere near enough information to diagnose this for you, but I can take a stab in the dark.
1) Driver. Windows will install default generic drivers for things like the chipset, but these won't always be a good match for the hardware. Install the latest drivers from your motherboards support website. All of them.
2) BIOS. The platform's still new and your motherboard may have BIOS updates available that resolve issues like this or improve performance or hardware compatibility.
3) Data corruption. Games today are typically downloaded, sometimes data gets corrupted in transit. If it's only one or two games that do this, try verifying the game files in Steam/Origin/etc.
4) Background activity. The problem could be a rogue background process or virus. Shutting down background tasks and unused services might help with the former - an offline virus scan like the Avira rescue CD will catch the latter.
5) Memory corruption. Easy but time consuming to check; run memtestx86 overnight. If it reports errors, try backing off your RAM timings or stepping down a speed tier.
6) Disk corruption. Windows stores some live data on disk in a process known as "swapping". This is more frequent on machines with less memory. A bad disk sector could cause data corruption if something gets stored in the bad sector, eventually leading to a recovery or crash. Windows has a built in tool to check disks for bad sectors - this article give a good run down on how to use it. Just be aware that this is a long process, so should probably be done overnight.
7) Final possibility is that PSU is underpowered for the hardware it's driving, causing voltage drops. This is the least likely option as most good power supply units have protections against it, but I've seen it once or twice.
