Asus ROG Phone II review

Thermals

Another thing we can't fail to mention and test while on the topic of performance on the ROG Phone II is the active cooling fan attachment that comes in the box. Just like on the original ROG Phone, it complements the specifically crafted internal heat pipe design of the phone, culminating in a small exposed radiator area. It not only ties in well into the gaming aesthetic, but also provides a convenient outlet for heat.

GeekBench 5 (multi-core)

Higher is better

• Asus ROG Phone II (X Mode + FAN)
  2830
• OnePlus 7 Pro
  2763
• Asus ROG Phone II (X Mode)
  2743
• Asus ROG Phone II (X Mode Ultimate + FAN)
  2696
• Asus ROG Phone II (120Hz)
  2396
• Samsung Galaxy Note10+
  2300

GeekBench 5 (single-core)

Higher is better

• Samsung Galaxy Note10+
  822
• Asus ROG Phone II (X Mode + FAN)
  771
• Asus ROG Phone II (X Mode Ultimate + FAN)
  763
• OnePlus 7 Pro
  744
• Asus ROG Phone II (X Mode)
  739
• Asus ROG Phone II (120Hz)
  736

As for real-life benefits from using the fan attachment are real and easily relateable to a gamer's needs.

The AeroActive Cooler II provides great sustained performance and comfort over prolonged gaming sessions.

That is to say that you won't really get any benchmark-breaking peek performance just from having the fan on the ROG Phone II. Rather a small, nifty bump up in numbers, if that. But you will definitely be able to sustain a higher and smoother average frame rate in games for longer, whereas otherwise thermal-throttling would inevitably set in. Plus, your hands will be a lot more comfortable and less sweaty while holding the phone and its metal frame, which gets particularly toasty in certain areas.

Throttling without fan

Just to illustrate the benefits of running an active fan, even one that sits on the outside of the phone to CPU thermals, here are a pair of throttling tests. Both done with X-Mode on Ultimate, the temperature slider all the way up, the screen set to 120Hz, with the AeroActive Cooler II being the only variable. The ROG Phone II was cooled in-between the runs.

Throttling with fan

During the first run without the AeroActive Cooler II the ROG Phone II held up maximum performance, or thereabout, valiantly all the way to about the 25 minute mark. At the end of the test the phone had retained 85% of its maximum performance. Making a few other calculations and adding the results to a performance pool from an earlier review, this is an amazing showing from the ROG Phone II.

Average performance over 1h as percentage of the max availabile

Higher is better

• Asus ROG Phone II (X Mode Ultimate + FAN)
  98%
• Asus ROG Phone II
  96%
• Black Shark 2
  92%
• nubia Red Magic 3 (fan)
  92%
• ZTE nubia Red Magic 3
  91%
• OnePlus 7
  90%
• Xiaomi Mi 9T
  88%
• Samsung Galaxy S10e
  75%
• Sony Xperia 1
  73%
• Xiaomi Pocophone F1
  67%
• Huawei P30 Pro
  64%

Minimal perforamnce over 1h as percentage of the max availabile

• Asus ROG Phone II (X Mode Ultimate + FAN)
  93%
• Black Shark 2
  89%
• nubia Red Magic 3 (fan)
  87%
• ZTE nubia Red Magic 3
  86%
• Asus ROG Phone II
  85%
• Xiaomi Mi 9T
  84%
• OnePlus 7
  83%
• Samsung Galaxy S10e
  64%
• Xiaomi Pocophone F1
  61%
• Huawei P30 Pro
  60%
• Sony Xperia 1
  48%

Even without the fan lending a hand, its cooling solution is clearly good enough to rank up there with the best including the nubia Red Magic 3, which does have a built-in active fan.

With the AeroActive Cooler II strapped on and going at full blast, the CPU Throttling test app actually reported no thermal throttling at all for the duration of the test. Something we frankly thought nearly impossible on a flagship smartphone.

As far as temperature goes, the surface of the ROG Phone II definitely gets toasty with prolonged loads, especially with X Mode Ultra and the temperature slider all the way up to high. That is kind of the idea of having these options available to the user and the price to pay for getting the ultimate performance. Even so, the quoted temperature was recorded at the exposed copper part of the internal cooler on the back of the phone. The only other unpleasantly hot spot on the device were certain parts of the frame, which reached 47 degrees.

Max surface temperature

Lower is better

• Asus ROG Phone II (X Mode Ultimate + FAN)
  51°
• Black Shark 2
  47°
• OnePlus 7
  47°
• Asus ROG Phone II
  46°
• Samsung Galaxy S10e
  46°
• Sony Xperia 1
  42°
• ZTE nubia Red Magic 3
  42°
• Xiaomi Pocophone F1
  39°
• Xiaomi Mi 9T
  39°
• nubia Red Magic 3 (Perf. mode + fan)
  37°
• Huawei P30 Pro
  37°

With the fan on and blowing, things got a lot more comfortable on every spot of the phone. Not only did the exposed vent cool down to 46 degrees, but the frame dropped to 44 and the rest of the body was a pretty manageable 36 degree average. Stressing once again that these numbers were reached using the most extreme settings and high thresholds available. Not only are they easily avoidable with more relaxed settings, but also unattainable in real world use cases.

The ROG Phone II represents the pinnacle of Android performance so far into 2019. Toss in the extensive accessory ecosystem that also provides tangible performance benefits in its own ways and you get a benchmark-setting and industry-leading, zero compromise gaming package.

Plus there is also, the unparalleled freedom an access to advanced fine-tuning tools provided to the user. The amount of optimization and tweaking that Asus themselves have put into the device is nothing short of impressive.