Lenovo ThinkPad X1 Extreme (i7, 4K-HDR, GTX 1050 Ti Max-Q) Laptop Review

Lenovo only ships the ThinkPad x1 Extreme with the new Intel WLAN module Wireless-AC 9560. It supports all common Wi-Fi standards and finally Bluetooth 5.0. We did not have any problems with the wireless network connection and the transfer rates are also very good. The sending performance was improved compared to the previous Wireless-AC 8265. Wired networks are handled by an Intel I219-V or I219-LM module (vPro SKUs), respectively.

We cannot understand why Lenovo drops a WWAN module for the X1 Extreme. Potential buyers of the smaller X1 Carbon already had to decide pre purchase for or against an LTE modem, because it was not upgradeable. It just makes no sense to waive the option for a flagship business laptop.

Lenovo's display selection is very similar to Dell, because you either get a matte 1080p IPS screen rated at 300 nits or the 4K screen (+354.62 Euros) from our test unit. The latter is brighter at 400 nits and is supposed to have wider color gamut. Similar to the smaller ThinkPad X1 Carbon, the screen also supports the playback of HDR contents, which is not possible on the rivals. It is also a touchscreen with pen support, but this also means the surface is glossy.

The subjective picture impression is very good and basically identical to the smaller ThinkPad X1 Carbon 2018 HDR. The 15.6-inch panel with the ID B156ZAN03.2 is provided by AU Optronics. We already mentioned the advertised brightness of 400 nits, but our test unit just misses this number. We determine an average luminance of 380 nits, which is on par with the HP EliteBook 1050 G1, while the other competitors from Dell and Apple are much brighter. The X1 Extreme gets points for the brightness distribution (90%) and the decent black value (0.28), which results in a very high contrast ratio (>1400:1). However, all the comparison devices are more or less on the same level.

You can notice some backlight bleeding around the edges on the two brightest settings, at least on dark contents. This is especially noticeable when you watch letterbox videos. We did not detect PWM on any brightness setting.

The Lenovo ThinkPad X1 Extreme is a powerful notebook, but the choice of components is limited compared to other ThinkPad models. You can choose between two quad-core (i5-8300H & i5-8400H) and two hexa-core CPUs (i7-8750H & i7-8850H) from Intel's Coffee lake generation. The two more expensive models (i5-8400H & i7-8850H) support Intel's vPro technology and are particularly important for larger companies. There is no Core i9 option, but this is not necessarily a bad thing with a slim chassis. The workstation sibling ThinkPad P1 is also available with Xeon processors (optional). You cannot change the GPU, which is always the Nvidia GeForce GTX 1050 Ti we already know from the Dell XPS 15. It is the more efficient Max-Q version with (supposedly) lower clocks. However, we already saw performance figures similar to a regular GTX 1050 Ti depending on the cooling solution. The X1 Extreme is only available with M.2-NVMe-SSDs, so the subjective performance impression is very good. We did not experience any latency issues with our test model.

The actual processor clock depends on the cooling capabilities as well as the TDP configuration, which can be adjusted by the OEMs. Lenovo selected rather conservative TDP limits below Intel's recommendation (55/78W). The CPU can consume up to 75W for short periods, but only 45W under sustained workloads. We performed our benchmarks with the default values, but we will also test with other TDP limits and reduce the core voltage as well (undervolting). For now, we start with the regular Cinebench scores.

The new ThinkPad X1 Extreme performs very well in the Cinebench R15 Multi test and is only beaten by the Dell XPS 15 9570 with the identical Core i7 processor but slightly higher TDP limits. Apple's MacBook Pro 15 2018 with the slightly faster Core i7-8850H on the other hand is a bit slower (even after Apple's major software updates). HP's EliteBook 1050 G1 is similar to the ThinkPad. Our test also shows the big gap compared to the ULV chips in the smaller ThinkPad X1 Carbon as well as the 15.6-inch ThinkPad T580, which fall behind by more than 40%.

There are, however, limitations on battery power. We set all the BIOS options to maximum performance, but the CPU cannot utilize its Turbo Boost and only runs at 2.0 GHz during the Cinebench R15 Multi test, which results in just 648 points.

It is always interesting to see how slim devices handle sustained workloads and not just short benchmarks with runtimes between 30-45 seconds. Our Cinebench Multi loop with 50 runs only shows a small drop of the score to ~1060 points, despite the conservative 45W limit. A more detailed analysis shows an average clock of 3.4 GHz for all six cores in combination with a core temperature of around 87 °C, so there is still some headroom. We ignore the undervolted results of the Dell XPS 15 for now (we will try this with the X1 Extreme as well) and see that the test model is ahead of the competition including the Apple MacBook Pro 15 with the supposedly faster i7-8850H.

There are two ways to improve the processor performance: Increase the TDP limits and reduce the core voltage (undervolting). Especially slim devices often have problems with increased TDP limits or are often already struggling with the original settings under sustained workloads. However, the 45W limit on the test unit of the X1 Extreme is rather conservative, so we set it to 57W for sustained workloads. We also reduced the core voltage at the same time with the tool Intel XTU. Please see our dedicated guide for detailed instructions on the undervolting process. Every processor is different and the results can vary. We managed to operate the Core i7-8750H at -0.165 mV, which has a massive effect on the power consumption and therefore the performance.

The processor now only needs about 50W for 6x 3.9 GHz during the Cinebench Multi test, and the system can maintain this level of performance. This results in excellent scores during our Cinebench loop, because all the results are north of 1200 points with two minor exceptions. The average results after 50 runs is 1.218 points. The CPU temperature is still 2 degrees lower. The ThinkPad X1 Extreme is therefore even better than the undervolted XPS 15, which was already very fast. The other rivals are clearly beaten. Our extreme torture test with Prime95 is even more stressful for the CPU and the full 6x 3.9 GHz require around 61W, but we still see strong 3.65 GHz once the 57W limit sets in. All in all a very good performance for a slim device.

The ThinkPad X1 Extreme can accommodate two M.2-2280 NVMe-SSDs (attached via PCIe-x4 each). Our test unit is equipped with Samsung's PM981 in the 1 TB configuration and you can use around 914 GB after the initial set-up. The performance of the storage drive is excellent and the write performance in particular is ahead of the competition. However, all models here have fast storage drives and you won't notice a subjective difference in practice. Lenovo uses different suppliers, so your X1 Extreme might be equipped with another drive. See our comprehensive HDD/SSD list for more benchmarks and comparisons.

There are more and more devices with the Max-Q version of the GeForce GTX 1050 Ti. We recently reviewed the efficient (and supposedly slower) version of the GTX 1050 Ti in the Dell XPS 15 9570. Nvidia has special requirements for Max-Q models (power consumption, fan noise during gaming), which are usually realized with lower clocks. However, the GTX 1050 Ti Max-Q in the XPS 15 was just as fast as a regular GTX 1050 Ti thanks to sufficient cooling capabilities. This is also the case for the ThinkPad X1 Extreme, because the official Boost frequency of 1291 MHz is clearly surpassed with up to 1695 MHz (Witcher 3).

Our test model is just behind the Dell XPS 15 with the same GTX 1050 Ti Max-Q in the synthetic 3DMark tests, but faster than the Radeon Pro 560X in the MacBook as well as the GTX 1050 Max-Q in the EliteBook 1050 G1; the X1 Extreme is between 14 - 38% faster depending on the benchmark. The smaller GeForce MX150 in the ThinkPad T580 is even slower. The X1 Extreme also passed the demanding Time Spy stress test without any problems (99.8%).

We already mentioned the integrated UHD Graphics 630 of the processor. Nvidia's Optimus technology automatically selects the graphics adapter based on the workload. The iGPU is much more efficient if you don't need the additional performance, and the powerful video decoder is also perfect for the playback of high-resolution videos/movies.

The GPU performance is slightly reduced on battery power with a graphics score of 6311 points compared to 7199 points on mains (3DMark Fire Strike).

The internal shots already showed the position of the two processors in the rear center area of the base unit. The fans are deactivated while idling, but the case still stays cool without any hot spots. Our thermal images under load illustrate the position of the CPU/GPU, the two fans next to them as well as the fan exhaust at the rear of the laptop.

These two spots are also the hot spots under load on the top or the bottom, respectively, and you should avoid direct skin contact with more than 50 °C at the bottom. However, the energy management does not seem to be perfectly optimized based on our test results. It seems Lenovo made a compromise to limit the fan noise. The stress test shows that the CPU has to reduce its clock very quickly, even though both the core temperature as well as the fan speed still have some headroom. The CPU only consumes about 15 Watts at the end of the stress test (which is only sufficient for 6x 1.0 GHz), while the GPU runs at the full speed for the whole test. If you stop the CPU load for a short while and then continue it, the clock will once again start at a higher level and then slowly drop back to 1.0 GHz (15W). This priority for the GPU performance benefits the gaming performance in particular. The processor is not stressed that much during gaming, so the performance is steady. This is also confirmed by our Witcher 3 longterm test. A 3DMark 11 run immediately after the stress test did not detect a performance deficit, either. This means there should not be any limitations in practice unless you fully stress both components simultaneously.

All in all, the performance under combined workloads is still a bit disappointing, but we hope Lenovo will offer an update. You could easily improve the CPU performance in this scenario with the maximum fan speed, which is not too loud at less than 40 dB(A).

The two speakers are located at the front sides of the bottom panel where the surface is slightly angled, so the sound is reflected towards the user on solid surfaces. Subjectively, the performance is decent and sufficient for some music and video playback. However, the performance could have been much better considering the empty space in the chassis. Both the XPS 15 as well as the Apple MacBook Pro 15 are superior in this respect.

The 3.5 mm stereo jack creates a noise-free signal and speakers or headphones can also be connected via Bluetooth, which worked well during our test.