Review Dell Inspiron 15-3521-0620 Notebook

Why always show off with aluminum, when a little bit less would have sufficed? In the last few years cases have become more and more high-grade. The OEMs know how to punch, brush and anodize aluminum. Through mass-production this procedure has been made available for the lower price-ranges. Nevertheless, it makes a difference in purchasing if plastic or an aluminum-plastic compound is ordered. When, in addition, high-quality hardware is offered at a low price point, there is nothing else the manufacturer can do but choose a low priced chassis.

To put it in a nutshell, our 15.6-incher is based on the same barebone as the more expensive 15R. Welcome to platform strategy. While the 15R is prettied up with an alu-interior and a cover made of the same material, the available basic model has none of it. To avoid scaring off the buyer with boring plastic, Dell has punched the surfaces with a haptically pleasing pattern. This pattern does not make the laptop less susceptible to fingerprints but the surfaces more scratch-proof and handier.

The base is adequately rigid, but can be bent under normal force within limits causing the case to twist in places like the optical drive. The lid can be dented slightly in the middle. The hinges are very tightly adjusted, it was impossible to open the laptop without using two hands. At about 130 degrees, the glare-type screen finds a reasonably solid position. Teetering of the opened lid can occur but not in an annoying manner.

Overall, the impression of quality is decent. What's bothersome though, are the many upwardly open cracks and joints (palm rest is fitted into the frame) which will eventually gather dust and dirt. The complete laptop has such a circumferential joint.

The hard drive and main memory can be replaced easily. To do so, a maintenance hatch at the bottom needs to be opened. However, the user has a hard time in accessing the fan for cleaning purposes.

Color spaces and TFT calibration are relevant to the professional target group that deals with image editing and printing. This is not the target group of the Inspiron 15, but we want to list the measurements for the sake of completeness. The smaller sRGB space is nowhere near complete coverage (52%), the same applies to the AdobeRGB (35%).

We have a closer look at the color display with the three CalMAN screenshots. We conducted a color analysis with the i1 Pro 2 photo spectrometer and the CalMAN 5 software prior to calibration. We spot an obvious weakness of the display of the shades of grey. All middle colorings are visible to the naked eye with a blue cast. The average DeltaE (2000) is at 10. Since the white point is also moved in the blue direction, the display is noticeably too cool.

The screen color saturation reveals that magenta, cyan and even red are slightly bluish. All of the three have a high DeltaE (2000) of <10. This means: The color deviations are clearly visible to the naked eye.

The CPU can be sped up to 2.7 GHz via Turbo Boost 2.0. This leads to a performance gain of the processor in comparison to the i3 (no turbo). The Cinebench CPU tests show a disadvantage of 8% for the Aspire E1-571G (i3). This is due to the standard voltage processor of this 15-incher. The IdeaPad Z580-M81EAGE (i5) and the V3-571G (i7) are comparatively better. In the multi-CPU test they throw an additional 16% and a considerable 145% respectively into the bargain. Those who are looking for high performance should turn to the 35 watts CPUs.

During the Cinebench R11.5 tests (multi & solo core), we also check if the CPU turbo is running properly. 2.5 GHz is constantly held during a multi-test, thus maintaining the turbo range (CPU temperature 63 °C). However, the GPU core permanently runs at 700 MHz during the OpenGL test. The measurements are correspondingly high, the GT 630M of the Z580 is beaten with a performance plus of 28%.

Hence the cooling system of the chassis can handle cooling the processor sufficiently. The performance stays at the exact same level during battery mode. All of the three Cinebench R11.5 tests score the same results.

PCMark and PCMark Vantage test the application performance. The result of 2119 points is figuratively at the very bottom. The competition scores 12 to 85% more. The Z580 is the only exception, despite the faster 35 watts processor. Theoretically speaking, the Z580 should fare slightly better, but the slower HDD prevents better scores. This, however, is also the case for our test device (HDD sub-score 1,455 and 2,837 points respectively). The throttling problem of the Lenovo competitor still remains, which might lower the performance to a low-voltage level.

Our test device by no means performs badly: Acer's Aspire V3-571G with quad-core i7-3610QM and powerful GeForce GT 640M runs only 15% quicker in the PCMark 7 test. From this perspective we cannot complain about the overall performance of our economical, entry-level laptop. By the way, HP's Pavilion Sleekbook 15 comes off that well (+85%) because it was equipped with a LiteOn LMT-32L3M as SSD cache to support the conventional HDD.

The temperature chart during idle reveals the positive impact of the low-voltage processor and the constantly running fan. The average is only 30 °C (top and bottom). Of course, this is not applicable for the temperature of the CPU and GPU during extreme high and long-lasting load (stress test). Now the top and bottom selectively heat up to 47/45 °C. Due to the counterbalancing cool areas, the average is still at only 39 °C (top) and 38 °C (bottom).

Unusual: constant 2.5 GHz CPU turbo

Throttling is not an issue for the test device. This would be quite disturbing for a 15-incher that could have been easily fitted with a 35 watts processor anyway. The clock speed in the stress test always lied above that of the nominal clock speed of 1.8 GHz, namely at 2.5 GHz (multi-core). The full CPU turbo is even activated under maximum GPU+CPU stress. At this setting the temperature of the CPU stays at 75 °C even after two hours. 3DMark06, which ran after the stress test, yields the same results as a cold boot.

The 15-incher is equipped with stereo speakers that are situated at the front underneath the palm rest. They reach a high volume but only with a brassy and clanking sound (especially at high volume). Since it does not own a subwoofer, we barely hear any low-pitched or bass sounds. Music sounds like a mishmash without any differentiations between high, medium and low ranges. This is a very disappointing performance for a multimedia notebook.

The Inspiron 15-3521 does not achieve the best runtimes with its 65 Wh lithium-ion battery despite the low-voltage hardware (good ultrabook 6-8 hours in the WLAN test). Four hours in this practical setting is not acceptable for the 15-incher. Despite the fact that they have less capacity and 35 watts CPUs, the competitors IdeaPad Z580 (48 Wh, 4:34 hours) and Aspire V3-571G (48 Wh, 3:16 hours) run longer (Z580) or compensate this disadvantage with more computing power (V3-571G).

It is standard practice to test the battery runtime when watching DVDs. With 2:04 hours this test ends even faster than the WLAN test. The second measurement, which played the movie from a hard drive, ended at 2:14 hours.

Given these short runtimes, the charge time of 3:45 hours is far too high (charging when device turned on, idle). This cannot be caused by excessive demands on the power supply which supplies 90 watts.