Another Test Shows Why Galaxy S26 Ultra Needs a Larger Vapor Chamber

Samsung’s Galaxy S26 Ultra is shaping up to be a powerhouse flagship for 2026. In all probability, it will use Qualcomm’s Snapdragon 8 Elite Gen 5 chip globally to deliver pro-level performance. Now, benchmark tests from a rival device using the same chip show why the Korean firm has reportedly improved its cooling system. This is a much-needed upgrade for delivering stable performance while keeping heat under control.

Stress tests reveal the Snapdragon 8 Elite Gen 5-powered phone can run hot

A few days ago, the folks over at Android Authority ran stress tests on the REDMAGIC 11 Pro and realme GT8 Pro. Powered by the Snapdragon 8 Elite Gen 5, both devices’ benchmark results showed that while the chip can deliver incredible performance, it also runs hot under sustained load. Now, the outlet has run the same testing on another Qualcomm flagship chip-powered phone (OnePlus 15), and the thermal behavior paints the same picture.

While OnePlus 15’s CPU performance is solid and matches other phones using the same chip in single-core GeekBench tests, the problems start during heavy GPU workloads. In the 3DMark stress test, the device reached a high temperature of 52.7°C, resulting in multiple shutdowns before the test could even finish.

Regarding the stress tests, a OnePlus spokesperson said, “In everyday use—whether multitasking or heavy-duty gaming—the units run within normal thermal limits; we’ve received no reports of excessive heat. Snapdragon 8 Elite Gen 5 delivers our highest peak performance yet, so in prolonged, all-out workloads it reaches the thermal ceiling sooner. We are already refining the thermal curve so that our peak performance remains uncompromised while surface temperatures stay comfortable.”

Meanwhile, Samsung may equip the Galaxy S26 Ultra with a customized version of the Snapdragon 8 Elite Gen 5. This variant may feature slightly higher clock speed on the prime cores (4.74GHz instead of 4.6GHz). While this boost could give the Ultra model an edge in performance, it carries the risk of excessive heat.

Thankfully, Samsung is expected to improve the S26 Ultra’s thermal design. Rumors suggest a larger vapor chamber, around 15% bigger than that of the predecessor. If true, this could help heat to dissipate from the processor more efficiently, resulting in stable performance during heavy workloads without overheating issues.