Dell Inspiron 15 5578 review – a good and robust 2-in-1 15-inch all-rounder

Looking into the realm of affordable 2-in-1s, the Inspiron 15 5578 from Dell sparks a lot of interest in us and it seems like a good competition to Lenovo’s Yoga 500-series. At this point, both options are similarly priced but which one will come out on top? Since they are all equipped with roughly the same hardware, it goes down to aesthetics, ergonomics and build quality.

At first glance, the Inspiron 15 5578 strongly reminds us of the Inspiron 13 7359 with the biggest difference being the screen size. While the latter will most likely appeal to more users due to its portable size, the 15-inch 5578 will surely win some user base looking for affordable and flexible 15-inch business solution. In this review, we will be looking at the updated Kaby Lake generation with Core i5-7200U CPU, a Full HD IPS panel and a standard storage configuration with a 2.5-inch HDD. If you are willing to spend a little bit more on the device, we suggest that you opt for the SSD configuration as it vastly improves performance.

You can find some of the available models here:


Retail package

The retail package offers the standard set of AC adapter, power cord, user manuals and the laptop itself.

Design and construction

As we already pointed out, the Inspiron 5578 features a design similar, if not identical, to its 13-inch sibling, the Inspiron 13 7359. The device is built mainly from plastic, weighs slightly less than you’d expect from a 15-inch laptop and it’s just around 20 mm thick. Still, it falls behind the Lenovo Yoga 510, for example, when it comes to weight. But in our opinion, Dell’s solution feels noticeably more robust than its competition.

The lid uses a plastic surface that feels quite sturdy and doesn’t give so easily under pressure and successfully imitates anodized aluminum. The only thing we dislike about this design are the ridiculously sharp corners of the notebook. Anyway, lifting the lid isn’t so easy because the metal hinges, which feel pretty nice, are a bit overly tightened and require both hands to open it up. And unfortunately, this isn’t enough to keep the screen from wobbling when in laptop mode. When tapping on the screen, you will see quite a bit of sway. The screen itself features fairly thin bezels with silicone strips along the sides so it won’t scratch when closing the lid. As for the bottom piece, it’s again made of plastic imitating anodized aluminum, two small grills for the stereo speakers and two big ones for extra airflow.

Even though this is a hybrid device, Dell doesn’t miss on the standard set of connectors. There’s one HDMI, two USB 3.0 and a 3.5 mm audio jack on the left while the right side accommodates only one USB 2.0 and an SD card reader. There’s no USB-C connector, unfortunately, but we doubt that this will be a deal-breaker since the standard isn’t so widely used… yet. The right side also holds the volume rocker and the power button, with the former protruding slightly more than the latter. We found ourselves reaching for the volume rocker more often than the power button.

The interior is probably the best part of this device and even makes us wonder why would anyone reach for the touchscreen instead of using the super responsive, accurate and huge touchpad. It’s also pleasantly clicky and stable while the keyboard’s travel seems a bit short but compensates with clicky and tactile feedback. The Numpad area is missing but the positioning of the keyboard this way makes a bit more sense. All of this makes up for a comfortable typing experience. Moreover, the plastic keyboard tray provides enough sturdiness and no flex occurs when pressed.

The only main disadvantages of the presented design would be the weight and the sharp corners. Both make the device a bit awkward to use in tablet mode but the size of the display looks great in presentation mode. Also, the wobbly screen is a bit of a let-down considering the tight hinges. In any case, you’d be delighted by the sturdiness of the Inspiron 5578 and its excellent input devices.

Disassembly, maintenance and upgrade options

The laptop doesn’t offer a dedicated service hatch but the bottom plate comes off easily and all of the hardware is there to reach. Just remove all the screws around the bottom and pry it up.

Storage upgrade options – 2.5-inch HDD/SSD

As expected, the notebook supports only a standard 2.5-inch HDD/SSD bay and in our case, it’s taken by a 1TB Seagate HDD.

Slot Unit Upgrade price
2.5-inch HDD/SSD 1TB Seagate HDD Upgrade options


The motherboard holds two RAM slots but only one of them was occupied on our unit. The chip is 8GB DDR4-2400 SK Hynix. Both slots can be found under the black caps as shown in the photos below.

Slot Unit Upgrade price
Slot 1 SK Hynix 8GB DDR4-2400 Upgrade options
Slot 2 Free Upgrade options

Other components

The Wi-Fi module is manufactured by Intel with model number 3165NGW.

The battery is found under the wrist rest area, as usual, and it’s rated at 42Wh.

Cooling system

The cooling design is very simple. There’s a single heat pipe connecting the heatsink and the cooling fan. The radiator is placed at the back of the machine and pushes the hot air out the back.

Display quality

The notebook comes with a 15.6-inch Full HD (1920×1080) touch-enabled IPS panel manufactured by LG with model number LG156WF7. The pixel density is 142 ppi while the pixel pitch is 0.18 x 0.18 mm so the screen can be considered as “Retina” when viewed from a distance equal or greater than 60 cm.

Viewing angles are good – there’s no noticeable shift under 45-degree incline.

The maximum brightness we were able to record is 240 cd/m2 in the center of the screen and 238 cd/m2 as average across the surface. This means that the deviation is just 7%. We’ve also measured the color temperature, which matches the standard 6500K perfectly. The contrast ratio is also really good – 1200:1.

We’ve measured the color deviation (dE2000) compared to the center of the screen and the result is just 2.2. This is considered as good because values above 4.0 are usually unwanted.

Color reproduction

To make sure we are on the same page, we would like to give you a little introduction of the sRGB color gamut and the Adobe RGB. To start, there’s the CIE 1976 Uniform Chromaticity Diagram that represents the visible specter of colors by the human eye, giving you a better perception of the color gamut coverage and the color accuracy.

Inside the black triangle, you will see the standard color gamut (sRGB) that is being used by millions of people in HDTV and on the web. As for the Adobe RGB, this is used in professional cameras, monitors etc for printing. Basically, colors inside the black triangle are used by everyone and this is the essential part of the color quality and color accuracy of a mainstream notebook.

Still, we’ve included other color spaces like the famous DCI-P3 standard used by movie studios, as well as the digital UHD Rec.2020 standard. Rec.2020, however, is still a thing of the future and it’s difficult for today’s displays to cover that well. We’ve also included the so-called Michael Pointer gamut, or Pointer’s gamut, which represents the colors that naturally occur around us every day.

Considering the price tag of the laptop, we were expecting a budget IPS panel and the sRGB coverage confirms that – the display can reproduce only 55% of the commonly used colors on the web and HDTV.

Below you will see practically the same image but with the color circles representing the reference colors and the white circles being the result. You can see main and additional colors with 25%, 50%, 75% and 100% saturation inside the sRGB gamut pre and post calibration.

We’ve created the “Office and Web Design Work” profile at 140 cd/m2, 6500K (D65) white point and gamma curve optimal for sRGB (2.2).

We tested the accuracy of the display with 24 commonly used colors like light and dark human skin, blue sky, green grass, orange etc. You can check out the results at factory condition and also, with the Office & Web Design profile.

The next figure shows how well the display is able to reproduce really dark parts of an image, which is essential when watching movies or playing games in low ambient light.

The left side of the image represents the display with stock settings, while the right one is with the Gaming & Movie Nights profile activated. On the horizontal axis, you will find the grayscale and on the vertical axis – the luminance of the display. On the two graphs below you can easily check for yourself how your display handles the darkest nuances but keep in mind that this also depends on the settings of your current display, the calibration, the viewing angle and the surrounding light conditions.

Response time

We test the reaction time of the pixels with the usual “black-to-white” and “white-to-black” method from 10% to 90% and reverse.

We recorded Fall Time + Rise Time = 28 ms.

PWM (Screen flickering)

Pulse Width modulation (PWM) is an easy way to control monitor brightness. When you lower the brightness, the light intensity of the backlight is not lowered, but instead turned off and on by the electronics with a frequency indistinguishable to the human eye. In these light impulses the light/no-light time ratio varies, while brightness remains unchanged, which is harmful to your eyes. You can read more about that in our dedicated article on PWM.

The display seems to be harmless in this regard as our equipment didn’t detect any flickering across all brightness levels.

Blue light emissions

Installing of our Health-Guard profile not only eliminates PWM but also reduces the harmful Blue Light emissions while keeping the colors of the screen perceptually accurate. If you’re not familiar with the Blue light, the TL;DR version is – emissions that negatively affect your eyes, skin, and your whole body. You can find more information about that in our dedicated article on Blue Light.

You can see the levels of emitted blue light on the spectral power distribution (SDP) graph.


Generally, the display is good, especially for this price range. It has the usual slightly above average sRGB coverage, the color accuracy is okay with the stock settings, the color temperature matches the optimal D65 white point and the contrast ratio is excellent. Also, our equipment didn’t detect PWM making the display suitable for long hours of work.

The only thing that may be of concern to the general user is the maximum brightness. The panel seems to be bright enough for working in well-lit closed environments but since it’s a 2-in-1 with glossy touchscreen, it won’t be sufficient for outdoor use under direct sunlight.

Buy our display profiles

Since our profiles are tailored for each individual display model, this article and its respective profile package is meant for Dell Inspiron 15 5578 configurations with 15.6″ LG LG156WF7 (FHD, 1920 × 1080) IPS touchscreen, which can be found at Amazon:

*Should you have problems with downloading the purchased file, try using a different browser to open the link you’ll receive via e-mail. If the download target is a .php file instead of an archive, change the file extension to .zip or contact us at [email protected]

Read more about the profiles HERE.

[edd_item edd_id_1=’81823′ edd_id_2=’81826′ edd_id_3=’81829′ edd_id_4=’81832′]


Our tests show that there’s enough clarity in the high, medium and low frequencies.

Specs sheet

The specs sheet provided below is for this model only and may vary depending on your region or configuration.

CPU Intel Core i5-7200U (2-core, 2.50-3.10 GHz, 4MB cache)
RAM 8GB (1x 8096MB) – DDR4, 2400MHz
GPU Intel HD Graphics 620 (Integrated)
HDD/SSD 1TB HDD (5400 rpm)
Display 15.6-inch Full HD (1920×1080) IPS touch, glossy
Optical Drive
Connectivity LAN 10/100/1000 Mbps, Wi-Fi 802.11ac, Bluetooth 4.2
Other features
  • 2x USB 3.0
  • 1x USB 2.0
  • HDMI
  • RJ-45
  • SD card reader
  • 3.5 mm audio jack
  • keyboard LED
Battery 42Wh
Thickness 20.2 mm (0.80″)
Weight 2.82 kg (6.22 lbs)


The notebook we’ve tested came with pre-installed Windows 10 (64-bit) but if you wish to perform a clean install of the OS, we suggest downloading the latest drivers from Dell’s official website.


Unfortunately, the battery performance is subpar. The 42Wh unit isn’t enough to keep the 15-inch FHD IPS display running for a long time. The CPU’s TDP of just 15W suggest that the chip itself isn’t the problem here.

Web browsing

In order to simulate real-life conditions, we used our own script to automatically browse through over 70 websites.

Way below average battery runtimes on the web browsing test – 245 minutes (4 hours and 5 minutes).

Video playback

For every test of this kind, we use the same video in HD.

The video playback time isn’t much different here – 214 minutes (3 hours and 39 minutes).


We recently started using the built-in F1 2015 benchmark on loop for accurate real-life gaming representation.

It’s quite unlikely that you will start a gaming session without being close to a power source, but it’s good to know that you can play a little bit over an hour – 72 minutes (1 hour and 12 minutes).

CPU – Intel Core i5-7200U

download-4Intel’s Core i7-6200U is part of the 7th Generation Kaby Lake CPUs and it’s the direct successor of the Core i5-5200U (Broadwell) and Core i5-6200U (Skylake). It’s also based on the same architecture as the aforementioned chips with little differences that should bring a small performance increase and a bump in power consumption. However, the new CPU is clocked at 2.5 GHz and its Turbo Boost frequency is 3.1 GHz opposed to the 2.3 – 2.8 GHz clocks on the previous Core i5-6200U.

Anyway, we still have the 2/4 core/thread count, 3MB last level cache, and a TDP of 15W, which includes the iGPU and the dual-channel DDR4 memory controller. Speaking of the former, the chip integrates the newer generation Intel HD Graphics 620 graphics chip clocked at 300 – 1000 MHz.

You can browse through our top CPUs ranking:

Here you will find other useful information and every notebook we’ve tested with this processor:

Fritz is a chess benchmark that tests the computing capabilities of the CPU with various chess moves. The Intel Core i5-7200U scored 6.395 million moves per second. In comparison, one of the most powerful chess computers, Deep(er) Blue, was able to squeeze out 200 million moves per second. In 1997 Deep(er) Blue even beat the famous Garry Kasparov with 3.5 to 2.5.

GPU – Intel HD Graphics 620

intel_hd_graphicsIntel’s HD Graphics 620 integrated iGPU can be found in various ULV (ultra-low voltage) processors from the Kaby Lake generation. The GT2 version of the graphics chip uses 24 EUs (Execution Units) that can be clocked up to 1050 MHz and it has a base frequency of 300 MHz but the former can vary depending on the CPU. Since the iGPU doesn’t have a dedicated memory of its own – or eDRAM for that matter – it uses the available RAM on the system which is 2x 64-bit DDR3 or DDR4.

The TDP depends on the CPU model but it’s usually equipped with a SoC rated at 15W including the memory controller.

You can browse through our top GPUs ranking:

Here you will find other useful information and every notebook with this GPU that we’ve tested:


Of course, the laptop isn’t made for extended heavy workload and we doubt that the CPU and iGPU will reach 100% load during normal use but these sort of stress tests that we perform are still the best way of assessing the overall stability and effectiveness of the cooling system.

The CPU stress test shows full CPU utilization – both cores were working at 3.0 GHz but temperatures were oddly high as you can see in the photo below.

After an hour, we turned on the GPU stress test as well. The CPU went down to 1.6 GHz to give enough headroom for the iGPU to perform.

Of course, temperatures on the surface remained pretty cool, which was expected since the hardware isn’t as demanding and powerful as some gaming laptops, for example.


The Inspiron 15 5578 is a good all-rounder with a few drawbacks that need to be considered. Build quality, however, isn’t one of them. The device surprises with firm and robust construction and excellent input devices. The keyboard is comfortable while the trackpad is precise and big enough to replace your external mouse. However, we have some concerns about the ergonomy and weight. The sharp corners make the device a bit uncomfortable to hold at times while the weight beats the purpose of a 2-in-1 hybrid.

In any case, we cannot miss mentioning the fact that it has a pretty good display with high contrast ratio, slightly above average sRGB coverage and it’s well calibrated out of the box. Moreover, we didn’t detect any PWM across all brightness levels making it suitable for long hours of work. Yet again, the maximum brightness will not be sufficient for outdoor usage.

And finally, you might want to consider the poor battery life if that’s of any concern to you. In any case, you should also consider looking into Lenovo’s Yoga 510 and HP’s Pavilion x360 15.

You can find some of the available models here:


  • Good build quality
  • Great input devices
  • Generally good IPS panel
  • PWM-free display


  • Sharp corners and a bit heavy for a 2-in-1
  • The display’s glossy surface and maximum brightness aren’t suitable for outdoor use
  • Poor battery life

Notify of
Inline Feedbacks
View all comments