Early reports have raised worries about Google's impending Pixel 9 Pro XL, since the device's Tensor G4 chip appears to have substantial thermal management issues, resulting in a dramatic loss of processing power under high loads. Initial CPU throttling testing show that the chip can lose up to 50 per cent of its performance within minutes of heavy use.
Google's own silicon, notably the Tensor series, has been subject to continual scrutiny for thermal performance, and the Pixel 9 Pro XL's Tensor G4 appears to be no exception. A user on X, @callmeshazzam, recently published the results of a CPU throttling test performed on their pre-ordered Pixel 9 Pro XL, which revealed disturbing conclusions. According to the test, the Tensor G4 chip encounters severe throttling after only three minutes of persistent load, with performance plummeting to 42.6 per cent of its peak capability.
The stress test monitored the frequency of the Tensor G4's eight CPU cores, revealing that the device originally achieved a peak speed of 341 giga instructions per second (GIPS), with an average output of 246.6 GIPS. However, under continuous stress, the chip's performance decreased rapidly, with the most aggressive throttling decreasing power to only 145.5 GIPS. The chip's frequency also decreased significantly, with performance cores falling to as low as 1.32 GHz and efficiency cores down to 570 MHz.
Although performance recovered after the initial drop, stabilising at roughly 65 per cent of its maximum capability, the test results indicate that Google may need to further optimise the Tensor G4's thermal management to avoid severe performance loss over extended operation.
Google has yet to declare official specifications for the Tensor G4, but previous Geekbench leaks suggested that the chip could include a single core clocked at 3.1 GHz, three cores at 3.6 GHz and four efficiency cores clocked at 1.95 GHz. While instructions per second (GIPS) is not the only measure of a chip's capabilities, the throttling test identifies potential issues that may affect real-world performance, particularly in demanding applications.
This isn't the first time Google's Tensor processors have faced criticism for temperature concerns. The Tensor series, which drives Google's Pixel lineup, has long been criticised for poor heat management and sustained performance under high loads. Despite this, Google has remained dedicated to developing bespoke silicon, focusing on the chips' AI capabilities and interaction with Google's software ecosystem.
The Pixel 9 Pro XL is likely to be Google's flagship device, with advanced computational photography, expanded AI functions and the latest Android software. However, these early reports indicate that prospective customers should be cautious of potential thermal throttling difficulties, particularly if they intend to use the device for intense tasks such as gaming or video editing.
As Google prepares for the Pixel 9 Pro XL's formal release, the firm will undoubtedly face additional pressure to resolve these concerns and ensure that the Tensor G4 chip delivers consistent performance across a wide range of use scenarios. Whether through software upgrades or additional hardware optimisations, Google's response to these initial findings will be critical in determining the device's success in an increasingly competitive smartphone market.