It powers the Dell Precision 15 mobile workstation tested here a few months ago. But these state-of-the-art processors cost a fortune. How would the same laptop perform without the pricey processor? Let’s take a look at the civilian version – the Dell XPS 15 9550 – to find out.
The Precision 15 and XPS 15 once again share the same solid chassis, except the XPS version takes a more familiar Core i5 or Core i7 Intel processor.
Importantly, the smart-looking aluminium and composite build of these notebooks is very sturdy, 20 mm thick* and weighing around 2.0 kg. But where the professional workstation cost over £2200 with its high-end silicon and 4K-UHD touchscreen, the basic consumer model reviewed here is half the price at £1099 (July 2016).
So the tough body remains the same, featuring an aluminium cover for the lid back and CNC-milled lower section, with a thin carbon-fibre veneer on the top deck around the keyboard. While carbon fibre sounds esoteric and space-age, its rubbery coating does pick up fingerprints all-too easily, leaving unsightly greasy patches to quickly mar its clean finish.
To hit the more accessible price on this entry-level XPS, economies are made to the main CPU, the graphics processor, storage and the screen – although controversially, the resulting notebook is a better product in certain key respects.
* Beware Dell’s mendacious measurements of ‘11-17 mm’. The corpus of this laptop is not less than 19.7 mm front and back
Intel processor first – the review sample was fitted with the 2.3 GHz Core i5-6300HQ option, which must be one of Intel’s first mobile quad-core chips taking the midrange ‘i5’ name. Until now, notebook quad-cores were all designated Core i7 (and confusingly, some higher-end mobile dual-cores too).
Unusually for a more potent quad-core, the Core i5-6300HQ is a straightforward four-core processor with no additional Hyper-Threading Technology to simulate an eight-core chip.
An alternative processor configuration for the XPS 15 is the Intel Core i7-6700HQ, otherwise the same but clocked 300 MHz faster (and with 3.5 GHz Turbo). And this time with Hyper Threading.
The Core i5 here still includes the familiar Turbo Boost facility, to a maximum of 3.2 GHz, and also incorporates a decent integrated graphics chipset – Intel HD Graphics 530 – that is specified by Intel as capable of 4K-UHD video at 60 fps through DisplayPort. Built using the latest 14 nm process, this complete Intel Core chip should offer good battery economy too.
The integrated Intel graphics chipset is only part of the story though, as Dell has also added a discrete Nvidia graphics solution in the form of the Nvidia GeForce GTX 960M, with 2 GB of fast GDDR5 video memory. This is designed to automatically take over on more graphics-intensive applications, like gaming, CAD work or GPGPU-capable software.
The GTX 960M is a popular and powerful consumer graphics chip, contrasting with the workstation-class Nvidia Quatro part found in the Precision workstation. In fact benchmarks revealed it’s potentially faster than the Precision’s Quatro M1000M in Windows games at least.
The same internal layout as the Precision means the XPS 15 can accept one 2.5in SATA drive and one M.2 SSD card, the latter either SATA or NVMe type. A significant economy is made in this cheapest configuration of the laptop, fitted with a single 7 mm-thick hard disk in the larger SATA bay. While its 1 TB capacity looks impressive, it will be the main bottleneck in day-to-day performance, so is best replaced with an SSD at the earliest opportunity; or an SSD can be specified when ordering from Dell’s online shop.
In testing, applications could be very slow to launch with this HDD storage, and I sometimes found Windows programs launching twice, after I’d clicked the app icon a few seconds later after no apparent reaction on first attempt.
(Note that the disk fitted to the sample was a regular 5400 rpm notebook disk, although Dell’s site now lists a hybrid drive that integrates 32 GB of flash storage. While these drives only accelerate some read operations it would likely help reduce some of the sluggishness I experienced.)
While Dell is keen to promote the glitzy 4K-UHD touchscreen version of its InfinityEdge display, the basic XPS model comes with arguably the better all-round option – a full-HD 1920 x 1080 IPS display with matt anti-glare finish. This provides much improved viewability thanks to its reflection-reducing coating, while the 1920 x 1080-pixel resolution is perhaps the best compromise when running Windows programs that do not scale correctly on higher-resolution panels. Not only does this display shave hundreds of pounds off the price (and around 100 g from the laptop’s overall weight), it’s also likely a reason why the XPS has better battery life than the touchscreen Precision.
Ins and outs
In common with the Precision 15, the left edge of the XPS 15 has its DC power inlet, one USB 3.0 port, USB 3.1 Type C and a 3.5 mm headset jack. On the right is a security lock slot, five-LED power level meter (activated by small button), another USB 3.0 and an SDXC card slot.
For wired ethernet an adaptor is required, either through USB 3.0 or the Type C port, and adaptors for the latter are now available for less than £20.
For video output, there’s an HDMI port, although this seems to be HDMI 1.4 spec so is best suited up to 2560 x 1600 pixels only – it will not support 60 fps video at full 4K-UHD (3840 x 2160-pixel) resolution.
However the new USB Type C ports should allow full 2160p/60 resolution using DisplayPort 1.2 as part of its Thunderbolt 3 specification. At least it should when required adaptors finally become available.
Meanwhile Dell’s own Thunderbolt Dock promised last year remains missing in action. This troubled unit was advertised as capable of running two 4K displays, but it looks to be discontinued before it even launched properly. Dell through its UK PR office has not answered my queries about this Dell Thunderbolt Dock.
To run one 4K-UHD display, it may be possible to use a Thunderbolt 3-to-Thunderbolt 2 adaptor such as sold by Startech.com.
I have no idea if this works correctly with UHD displays though, and it will cost the buyer £110 to find out. Another possibility is a mooted £99.95 adaptor from Kanex, the Thunderbolt 3 to Thunderbolt Adapter.
For wireless connectivity, this XPS model came fitted with a Dell Wireless 1830, which combines 802.11ac and Bluetooth 4.1 on one Mini-PCIe card. This item looks to be based on the Broadcom BCM43602 SoC, and is specified with 3×3:3 three-antennae/three-stream capability – an unusual fitting given that Windows laptops have been lucky to see even 2×2 configurations until recently. The full 3×3 array should allow nominal wireless sync speeds of 1300 Mb/s given a suitable 11ac wireless router.
Focusing on the main CPU and its supporting 8 GB of DDR4 2133 MHz memory, the XPS 15 scored 3463 points in Geekbench 3, rising to 10,073 points using four cores. That trails the 3807 and 14,132 points garnered by the Precision 15, but that shouldn’t be too surprising given that notebook’s 2.6 GHz Intel Xeon with Hyper Threading.
The gap widened in Cinebench, the XPS returning 128 and 470 points for single- and multi-core, against the Precision’s 151- and massive 732-point results. The XPS’ Cinebench rendering results are still impressive though, especially when set against a mobile workstation like the HP ZBook 14 with its humble dual-core processor.
In the OpenGL rendering test, the XPS 15 ran at 86 fps, where the Precision 15’s Quatro professional card proved its worth with 101 fps.
What is less easy to explain is how the XPS 15 scored above the Precision 15 when tested with PCMark 8. Here the consumer machine returned 2908 points in the Home test (and 3391 with GPU acceleration), beating the 2807 points (3086 accelerated) from the pro-build Precision. That’s all the more remarkable given not just the faster CPU in the Precison, but the latter’s SSD storage which is usually a significant factor in the Futuremark real world-style application tests.
Windows gaming with XPS 15 and its Nvidia GTX 960M graphics will not be a problem. Presented with the Batmark (Batman: Arkham City) the XPS played effortlessly at maximum quality and native screen resolution at 62 fps, with minima still at 37 fps.
Tomb Raider (2013) proved a little more challenging for the Dell, averaging 53 fps at Ultra detail and full-HD res, then drooping to 35 fps at top Ultimate settings. This also saw a minimum of 27 fps, so keeping to Ultra could be prudent here.
And now comes even better news. The Sharp LQ156M1 display proved one of the best currently available, an in-plane switching panel measured with an impressive 960:1 contrast ratio from an honest chequerboard test. And colour accuracy test showed an excellent Delta E average error of just 0.7. The XPS 15 with its full-HD screen had a colour gamut close to full sRGB at 96 %, and 74 % of AdobeRGB.
As can be expected from a good IPS panel, colour images looked rich and natural; the high contrast ratio made black text especially well-defined and legible; and viewing angles were extended almost 180 º from side to side. For the matt-screen model, the troublesome alumino-silicate cover (‘Gorilla Glass’) has been omitted, leaving the panel seemingly recessed an extra millimetre or so. But this option maintains the unusually thin bezel around the top and sides, just 5.4 mm wide, which Dell describes as its ‘virtually borderless InfinityEdge display’. It provides a great window into the computer interface and helps to keep overall hardware size smaller too.
Dell’s online spec laughably lists 17 hours of battery life, only referencing this result as coming from MobileMark 2014. In the standard rundown test, streaming HD video over Wi-Fi with screen at 120 cd/m2, the XPS 15 with its 56 Wh battery lasted for a useful 6 hours 14 minutes. That compares well with the limited 4 hr 09 mins from the Precision 15, and means the XPS could last around half a regular working day before requiring a recharge.
The 100 words or less
Dell has a winner with the XPS 15, a well-crafted 15-inch laptop available with top-quality IPS matt screen and the latest 6th-generation Intel Core processors. The Nvidia graphics aren’t so brand-new but crucially are beyond capable for most gaming requirements. Battery life is not bad at around six hours, and the selection of ports includes a Thunderbolt 3/Type C USB that’s so new it’s not proving easy to find the adaptors to enable its use yet. For anyone that must have a 15-inch Windows laptop, this is the machine to beat. AH
Specification as tested:
15.6-inch (1920 x 1080) 141 ppi IPS matt anti-glare (Sharp LQ156M1); Windows 10 Home; 2.3 GHz Intel Core i5-6300HQ, 3.2 GHz Turbo (4C/4T); Nvidia GeForce GTX 960M with 2 GB GDDR5 + Intel HD Graphics 530; 8 GB (2x 4 GB) DDR4 2133 MHz SDRAM; 1 TB 2.5in SATA HDD, 5400 rpm, 7 mm (Toshiba MQ02ABF100); 802.11ac Wi-Fi (Dell Wireless 1830); Bluetooth 4.1; 2x USB 3.0, 1x USB 3.1 Gen 2 Type C; HDMI; security lock slot; SDXC card slot; stereo speakers; 0.9 megapixel lower bezel webcam; dual mics; 3.5 mm headset jack; UK tiled keyboard with two-level white backlight; 105 x 80 mm buttonless trackpad; 56 Wh lithium-ion battery, non-removable; 130 W mains adaptor; 357 x 235 x 19.7 mm; 1938 g