We stress test all custom PC systems for at least 24 hours, if we find any issues we will tweak the bios, fan tuning and we might even tweak the CPU settings slightly (with your consent) to ensure reliable performance. We are big on airflow, so most of our cases on our website are designed for the best airflow, this keeps system temperatures cool and improves reliability. The stress tests heat the system far beyond what you will do to it, so you can rest assured it will be the best it can be as soon as you turn it on.