Honestly, been overclocking for years, and the honest truth is you are better off using benchmarks for a "general" stability test. It doesn't matter if ran *insert program here* for 3 days straight with zero crashes/errors, you can fire up a game and crash within minutes(been there so many times that I gave up using ANY benchmark or stability testing program as a definitive stability) . If you get your overclock to what seems like a stable state with **insert benchmark/stability test here**, dedicate the next couple days to playing some demanding titles for as many hours as possible, making sure you get a good 6+ hour session of your favorite demanding game in. Always remember too that summer will be here before you know it, and will likely mean increased ambient temps.
My last personal PC build(sig rig) I spent days playing around tweaking & tuning. Using Benchmarks such as 3DMark, Cinebench, CPU-Z bench/stress, Intel Burn Test(best in my book for CPU stability), eVGA OC Scanner, Memtest86. I finally got everything passing flying colors. Temps were good, no errors or crashes in ANY benchmark. I fired up Crysis 3, and after about 45min of gameplay, I had my first crash(cpu needed more voltage) =\ So hours of hours of dedicated benchmarking, only to have a AAA title game to show 3Dmark how to properly tax a system. I guess that's why they ask "But can it run Crysis"
All my babbling aside, all I am really saying is don't spend countless hours/days stability testing with Synthetic benchmarks, use them as a baseline. Take the time to play your favorite games & see how they run & if they crash. Best of luck