If you're looking for a more budget-friendly option for general use like web browsing and office applications, the Dell Inspiron 15 3520 will be sufficient and lighter on your wallet. However, if you need higher performance for activities like 3D rendering, machine learning, or gaming, the Lenovo Legion Slim 7 is more suitable despite being more costly. The Lenovo also offers better battery life and a higher-quality screen, but it is slightly heavier, which could be a consideration if you need to carry it around frequently. Both have 15.6-inch displays, but the Lenovo's finer qualities command a higher price. Give Feedback
this description is based on the product variant with some specs and product variant with some specs. At the time of writing, the variant with some specs cost some dollars and the variant with some specs cost some dollars.
Advantages of the Dell Inspiron 15 3520
The Dell Inspiron 15 3520 has no clear advantages over the Lenovo Legion Slim 7 15.6".
Advantages of the Lenovo Legion Slim 7 15.6"
Good for general use
Good for engineering and design
Good for gaming and AI
Good for software development
Good overall display quality
Good overall build quality
Very good speakers
Very good keyboard
Key differences
General Use
6.9/10
7.7/10
1920 x 1080
RESOLUTION
1920 x 1080
IPS
DISPLAY TECHNOLOGY
IPS
259.0 nits
DISPLAY BRIGHTNESS
350.0 nits
6.5 Hours
BATTERY LIFE
9.0 Hours
6.5/10
KEYBOARD QUALITY SCORE
8.5/10
7.6/10
PORTABILITY SCORE
7.6/10
The Lenovo Legion Slim 7 15.6" is good for general use, while the Dell Inspiron 15 3520 is only fair.
The Dell Inspiron 15 3520, with an Intel i3 processor and 8 GB of RAM, struggles with multitasking and complex applications compared to the Lenovo Legion Slim 7, which has a more powerful AMD Ryzen 7 processor and double the memory, resulting in smoother performance. While both have similar screen quality and size, the Legion Slim 7 also boasts superior battery life, a lighter build, and better heat management, making it better for general use but with a potentially higher price point.
Gaming and AI
6.0/10
7.4/10
3.6/10
OVERALL GPU SCORE
7.1/10
1920 x 1080
RESOLUTION
1920 x 1080
120Hz
REFRESH RATE
165Hz
No
SUPPORTS DLSS
Yes
No
MUX SWITCH / ADVANCED OPTIMUS
Yes
7.5/10
FAN NOISE SCORE
7.5/10
The Lenovo Legion Slim 7 15.6" is good for gaming and AI, while the Dell Inspiron 15 3520 is only fair.
The Dell Inspiron 15 3520 is less suited for gaming and 3D because it has a basic Intel UHD Graphics, which is less powerful than the Nvidia RTX 3060 GPU found in the Lenovo Legion Slim 7, which also offers a higher screen refresh rate conducive to smoother gaming visuals.
Engineering and Design
6.3/10
7.8/10
5.8/10
OVERALL CPU SCORE
7.4/10
3.6/10
OVERALL GPU SCORE
7.1/10
8.0 GB
RAM
16.0 GB
The Lenovo Legion Slim 7 15.6" is good for engineering and design, while the Dell Inspiron 15 3520 is only fair.
The Dell Inspiron 15 3520 is fair for engineering and design because it has modest specs like an Intel i3 processor and integrated graphics, which can handle some tasks but may struggle with more complex software used in those fields. In contrast, the Lenovo Legion Slim 7 offers a more powerful AMD Ryzen 7 CPU and Nvidia RTX 3060 GPU, better suited for demanding tasks and providing superior screen quality, making it good for engineering and design applications.
Content Creation
7.0/10
7.7/10
5.8/10
OVERALL CPU SCORE
7.4/10
1920 x 1080
RESOLUTION
1920 x 1080
8.0 GB
RAM
16.0 GB
IPS
DISPLAY TECHNOLOGY
IPS
The Lenovo Legion Slim 7 15.6" and Dell Inspiron 15 3520 are both good for content creation, though the Lenovo Legion Slim 7 15.6" is somewhat better.
PerfectRec’s Content Creation Score takes into account the many different features of the laptop that make it more or less suitable for photo editing, video editing and other content creation tasks.
Software Development
6.7/10
7.5/10
5.8/10
OVERALL CPU SCORE
7.4/10
8.0 GB
RAM
16.0 GB
1920 x 1080
RESOLUTION
1920 x 1080
6.5/10
KEYBOARD QUALITY SCORE
8.5/10
The Lenovo Legion Slim 7 15.6" is good for software development, while the Dell Inspiron 15 3520 is only fair.
PerfectRec’s Software Development Score takes into account the many different features of the laptop that make it more or less suitable for software developers.
Screen Quality
6.8/10
7.7/10
15.6in
SIZE
15.6in
1920 x 1080
RESOLUTION
1920 x 1080
IPS
DISPLAY TECHNOLOGY
IPS
120Hz
REFRESH RATE
165Hz
259.0 nits
BRIGHTNESS
350.0 nits
The Lenovo Legion Slim 7 has a better screen than the Dell Inspiron 15 3520 for general use, gaming and AI, engineering and design, content creation, and software development.
For general use, the Dell Inspiron 15 3520's screen offers adequate resolution and brightness, but it may lack the vibrancy and wide viewing angles of higher-end panels. The Lenovo Legion Slim 7, with a superior panel, higher resolution, and greater brightness, provides a more pleasing visual experience for tasks like browsing and document editing. However, while both laptops have screens suitable for engineering and design due to respectable color coverage, neither is optimal for gaming or 3D work because they lack high refresh rates necessary for smooth motion rendering.
Battery
6.5 Hours
9.0 Hours
The Dell Inspiron 15 3520 has 6.5 hours of battery life. The Lenovo Legion Slim 7 has 9 hours of battery life.
Battery life estimate is based on a mix of common use patterns. More portable and higher performing laptops tend to have less battery life.
Build Quality
6.2/10
7.6/10
The Lenovo Legion Slim 7 15.6" has good build quality, while the Dell Inspiron 15 3520 has only fair build quality.
PerfectRec’s Build Quality Score incorporates case materials, display and keyboard flex, hinge quality, and overall reliability.
Cost
$335
$1,200
$0
$500
$1,000
$1,500
$2,000
The Dell Inspiron 15 3520 has a price of $335 and the Lenovo Legion Slim 7 15.6" costs $1,200.
"Dell's Inspiron 15 (3525) is a peppy-enough and affordable-enough home or remote work machine, but it's not very ambitious; it does little to go beyond the basics. More the concern: It’s readily overshadowed by a number of machines that outperform and outclass it. Even if the Inspiron can get the job done today, its competition has the mettle to keep doing the job tomorrow in a way the Inspiron simply can’t promise. Plus, those alternatives are much more enjoyable after work."
"The Lenovo Legion Slim 7 is a slim Legion notebook that is just as excellent with Nvidia & Intel. However, the Legion Slim 7i slightly sullied by lacklustre battery life. You get a slim aluminium chassis, great input devices, decent port selection, fast high-quality WQXGA display and great performance. Supporting Thunderbolt 4 is one advantage of the Intel/Nvidia model tested in this review. Moreover, this variant has slightly higher CPU performance as well as better GPU performance in certain applications (e.g. CUDA-based apps). The Lenovo Legion S7i is thin, premium and performant – but less efficient than its AMD counterpart."
Get a great deal on the Dell Inspiron 15 3520 or the Lenovo Legion Slim 7 15.6"
About Dell
Dell is a highly recognizable American technology company, and is one of the largest personal computer vendor by market share. Their laptops are very popular for both personal and professional use, and they also own the Alienware brand which makes mid to high end gaming laptops. Their premium XPS range of laptops offer great build quality and portability, while Latitude and Precision laptops are known for reliability, repairability and performance for business users.
About Lenovo
Lenovo is a Chinese technology company, and one of the largest personal computer vendor. They are well known for a variety of technology products, including laptops. Their consumer series include their entry level IdeaPad and LOQ series and mid-to-high-end Yoga and Legion series. On the business-oriented side, their series include their entry-level ThinkBook series and mid-to-high-end ThinkPad series. Lenovo laptops offer strong performance for reasonable prices, and are often on sale.
This information was produced and vetted by the PerfectRec laptops team. We are a product research and recommendation organization that meticulously reviews and evaluates the latest laptop information and makes it digestible for you.
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