OnePlus 15 overheating fix tested — here are the results

When we initially reviewed the new OnePlus 15, we found that the phone’s Snapdragon 8 Elite Gen 5 was too hot to complete our usual stress test benchmarks. At the time, OnePlus stated that it was “refining the thermal curve” and has since issued an update to the handset, claiming it has addressed the problem. So we’ve updated our handset and re-run the tests to find out.

Before conducting the stress tests, we re-ran the OnePlus 15 through GeekBench 6 to verify that the phone’s overall performance profile hadn’t changed. The good news is that CPU performance remains just as good, if not marginally better (though a 1.5% to 2% improvement is within the margin of error) than before the update. Flicking on the phone’s performance mode is actually closer to 5% faster in multi-core.

When it comes to 3DMark’s graphics test, performance is actually higher in both Solar Bay and Wild Life Extreme compared to the pre-update tests we ran. That’s good news; OnePlus hasn’t labotomised the phone to keep it cooler.

OK, so what about the stress test results? Well, the test actually completed this time, which is a major improvement compared to last time’s overheating and force-closing of applications. Temperatures now peak in the region of 47°C (117°F) internally compared to the 52.7°C (127°F) external temperature we recorded the first time around.

That’s still pretty hot, but far closer to what we’ve come to expect from these rather extreme stress tests on top-tier chipsets. Now that it’s running, let’s compare the OnePlus 15 to the realme GT8 Pro — another Snapdragon 8 Elite Gen 5 handset — and the OPPO Find X9 Pro, its sister phone powered by the MediaTek Dimensity 9500.

Following the update, the OnePlus 15 follows a very familiar trajectory as other recent high-end smartphones powered by a top-tier chip. Initial performance starts very strongly, but it only takes a few minutes of high GPU load to trigger throttling, which reduces performance.

By the end of the test, the OnePlus 15 drops to about 60% of its highest score — not brilliant, but certainly not a disaster either. However, this does mean that its sustained performance tracks very closely to last year’s OnePlus 13, sometimes slightly above and sometimes slightly below. While the OnePlus 15 boasts higher peak performance than its predecessor, longer gaming sessions and emulation may not yield improvements over last year.

Temperature-wise, the OnePlus 15 is slightly cooler than the realme GT8 Pro in the first few rounds of each test. This allows the phone to sustain higher performance for a little longer than its Snapdragon rival, which should translate into a slightly smoother experience for more demanding gaming sessions. By the end of 20 runs, the temperatures are pretty much identical, but the OnePlus 15 offers more consistent performance, so it can definitely chalk that up as a significant win.

However, the phone’s temperatures are still higher than the OPPO Find X9 Pro and its alternative premium-chip configuration. The OPPO peaks at about 39.7°C (103.5°F) while delivering equivalent, if not slightly better, average performance in these tests. That being said, the OPPO has a lower worst-case performance of just 44.5% of its peak.

After retesting, it’s clear that OnePlus has made significant progress in addressing the OnePlus 15’s early thermal issues. The update doesn’t fundamentally alter the phone’s performance profile — if anything, it adds a slight bump — while finally allowing it to complete demanding stress tests without overheating or force-closing apps. Temperatures remain on the warm side, but they now fall within a common and just about acceptable range for a Snapdragon 8 Elite Gen 5 device under extreme load.

In sustained performance, the OnePlus 15 behaves much more like its flagship peers, even outpacing the realme GT8 Pro under stress thanks to a slightly better thermal start. It still can’t quite match the cooler, more efficient operation of the OPPO Find X9 Pro, but that’s a topic worth an article in itself.

The OnePlus 15 still isn’t the most stable Snapdragon 8 Elite Gen 5 flagship we’ve tested (you need liquid cooling for that), but the update transforms it from an outlier into something closer to the level of performance we initially expected. However, we still need to investigate what this update means for real-world games and, in particular, the most demanding emulators that you might throw at the phone.