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Updated January 10, 2024·
The Dell Alienware m15 R7 offers high performance for intensive engineering tasks, gaming, and machine learning but it is expensive and less portable with shorter battery life. In contrast, the Lenovo Legion Slim 5 is more affordable, relatively lightweight, and has longer battery life, making it good for general use and suitable for some gaming and engineering, but with less powerful hardware than the Alienware, it may not handle the most demanding tasks as effectively. Choose the Alienware if top performance and gaming are priorities, or the Legion Slim 5 for better battery life and portability with competent but not top-tier performance. 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 Alienware m15 R7
- Very good overall display quality
- Very good overall build quality
Advantages of the Lenovo Legion Slim 5
- Good battery life
Key differences
Screen Quality
8.2
7.2
15.6in
SIZE
16.0in
2560 x 1440
RESOLUTION
1920 x 1200
IPS
DISPLAY TECHNOLOGY
IPS
240Hz
REFRESH RATE
144Hz
300.0 nits
BRIGHTNESS
300.0 nits
The Dell Alienware m15 R7 has a better screen than the Lenovo Legion Slim 5 for general use, gaming and AI, and engineering and design.
The Dell Alienware m15 R7 stands out for general use and engineering with its high resolution and bright display, enhancing sharpness and visibility, while the wide color gamut ensures accurate colors for design work. However, its lower refresh rate hampers gaming and 3D tasks, where fluid motion is crucial. The Lenovo Legion Slim 5 provides a balanced display with sufficient resolution and brightness for everyday tasks and design, but like the Alienware, the refresh rate is not optimized for the smooth visuals demanded by high-speed gaming and 3D applications.
Battery
5.0 Hours
7.0 Hours
The Dell Alienware m15 R7 has 5 hours of battery life. The Lenovo Legion Slim 5 has 7 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
8.5
7.4
The Dell Alienware m15 R7 has very good build quality, while the Lenovo Legion Slim 5 has good build quality.
PerfectRec’s Build Quality Score incorporates case materials, display and keyboard flex, hinge quality, and overall reliability.
Cost
$2,200
$1,000
$500
$1,000
$1,500
$2,000
$2,500
$3,000
$3,500
The Dell Alienware m15 R7 has a price of $2,200 and the Lenovo Legion Slim 5 costs $1,000.
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Key similarities
General Use
7.5
7.6
2560 x 1440
RESOLUTION
1920 x 1200
IPS
DISPLAY TECHNOLOGY
IPS
300.0 nits
DISPLAY BRIGHTNESS
300.0 nits
5.0 Hours
BATTERY LIFE
7.0 Hours
8.5/10
KEYBOARD QUALITY SCORE
8.5/10
6.4/10
PORTABILITY SCORE
6.7/10
The Lenovo Legion Slim 5 and Dell Alienware m15 R7 are both good for general use.
The Dell Alienware m15 R7 offers strong performance with a high-end CPU and graphics card, ideal for tasks requiring significant power, but its heavier weight and shorter battery life may limit its portability for general use. Meanwhile, the Lenovo Legion Slim 5 provides good performance for everyday tasks, benefits from a lighter design for easier portability, and offers a longer battery life, making it suitable for users who prioritize mobility and all-day use.
Gaming and AI
7.8
7.7
8.7/10
OVERALL GPU SCORE
8.4/10
2560 x 1440
RESOLUTION
1920 x 1200
240Hz
REFRESH RATE
144Hz
Yes
SUPPORTS DLSS
Yes
Yes
MUX SWITCH / ADVANCED OPTIMUS
Yes
7.0/10
FAN NOISE SCORE
6.5/10
The Dell Alienware m15 R7 and Lenovo Legion Slim 5 are both good for gaming and AI.
The Dell Alienware m15 R7, equipped with an Nvidia RTX 3070 Ti and a screen refresh rate of 240 Hz, provides a superior gaming experience for smoother motion and better detail than the Lenovo Legion Slim 5, which features an Nvidia RTX 4060 and a refresh rate of 144 Hz. While both are capable for 3D and gaming, the Alienware's higher-tier GPU and refresh rate cater to the needs of more demanding games and 3D applications.
Engineering and Design
8.2
8.0
8.5/10
OVERALL CPU SCORE
8.3/10
8.7/10
OVERALL GPU SCORE
8.4/10
16.0 GB
RAM
16.0 GB
The Dell Alienware m15 R7 and Lenovo Legion Slim 5 are both very good for engineering and design.
The Dell Alienware m15 R7 is equipped with a high-end CPU and a more powerful GPU suitable for demanding engineering and design tasks, and features a high-refresh rate screen enhancing visual clarity and fluidity. Whereas, the Lenovo Legion Slim 5, while also possessing a solid CPU and GPU for engineering, stands out with its higher screen resolution and portability, making it a versatile option for both work and mobility with a slightly slimmer and lighter design.
Content Creation
7.5
7.5
8.5/10
OVERALL CPU SCORE
8.3/10
2560 x 1440
RESOLUTION
1920 x 1200
16.0 GB
RAM
16.0 GB
IPS
DISPLAY TECHNOLOGY
IPS
The Lenovo Legion Slim 5 and Dell Alienware m15 R7 are both good for content creation.
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
7.3
7.4
8.5/10
OVERALL CPU SCORE
8.3/10
16.0 GB
RAM
16.0 GB
2560 x 1440
RESOLUTION
1920 x 1200
8.5/10
KEYBOARD QUALITY SCORE
8.5/10
The Lenovo Legion Slim 5 and Dell Alienware m15 R7 are both good for software development.
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.
Portability
Fair
Fair
15.6in
SIZE
16.0in
5.9 lbs
WEIGHT
5.2 lbs
0.9in
THICKNESS
0.9in
The Lenovo Legion Slim 5 and Dell Alienware m15 R7 both have only fair portability.
The most portable laptops are small, thin, and light.
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How the Dell Alienware m15 R7 and the Lenovo Legion Slim 5 compare to other laptops
Spec Comparison
 |  | |
| Dell Alienware m15 R7 | Lenovo Legion Slim 5 |
GENERAL | |||
|---|---|---|---|
| Price | |||
$2,200 | $1,000 | ||
Release Date | |||
Release Date | May 1, 2022 | May 1, 2023 | |
Overall Dimensions | |||
Overall Dimensions | 14'' x 10.7'' x 0.94'' | 14.2'' x 10.3'' x 0.99'' | |
Weight | |||
Weight | 5.93 lbs | 5.29 lbs | |
Width | |||
Width | 14.02" | 14.16" | |
Depth | |||
Depth | 10.73" | 10.25" | |
INTERNAL | |||
|---|---|---|---|
Processor | |||
Processor | AMD Ryzen 9 6900HX | AMD Ryzen 5 7640HS | |
RAM | |||
RAM | 16 GB | 16 GB | |
DDR Memory Version | |||
DDR Memory Version | 5 | 5 | |
RAM Slots | |||
RAM Slots | 2 | 2 | |
Storage | |||
Storage | 512 GB | 512 GB | |
BATTERY | |||
|---|---|---|---|
Battery Life | |||
Battery Life | 5 Hours | 7 Hours | |
Battery Capacity | |||
Battery Capacity | 86 Wh | 80 Wh | |
SCREEN | |||
|---|---|---|---|
Diagonal Size | |||
Diagonal Size | 15.6" | 16" | |
Display Technology | |||
Display Technology | IPS | IPS | |
Resolution | |||
Resolution | 2560 x 1440 | 1920 x 1200 | |
Refresh Rate | |||
Refresh Rate | 240Hz | 144Hz | |
Display Brightness | |||
Display Brightness | 300 nits | 300 nits | |
RELIABILITY, APPEARANCE & ACOUSTICS | |||
|---|---|---|---|
Build Quality Score | |||
Build Quality Score | 8.5/10 | 7.4/10 | |
Portability Score | |||
Portability Score | 6.5/10 | 6.7/10 | |
Gaming Laptop Appearance | |||
Gaming Laptop Appearance | Yes | Yes | |
Premium Business Laptop | |||
Premium Business Laptop | No | No | |
Fan Noise Score | |||
Fan Noise Score | 7/10 | 6.5/10 | |
HARDWARE FEATURES | |||
|---|---|---|---|
Keyboard Quality Score | |||
Keyboard Quality Score | 8.5/10 | 8.5/10 | |
Speaker Quality Score | |||
Speaker Quality Score | 7.5/10 | 7/10 | |
Webcam | |||
Webcam | 720p | 1080p | |
Fingerprint Reader | |||
Fingerprint Reader | No | No | |
Backlit Keyboard | |||
Backlit Keyboard | Yes | Yes | |
Number Pad | |||
Number Pad | No | Yes | |
CONNECTIVITY | |||
|---|---|---|---|
USB Type-A | |||
USB Type-A | 3 | 2 | |
USB-C ports | |||
USB-C ports | 1 | 2 | |
USB-C Charging | |||
USB-C Charging | No | Yes | |
Display Outputs | |||
Display Outputs | 2 | 3 | |
Thunderbolt Ports | |||
Thunderbolt Ports | 0 | 0 | |
Shopping
Dell Alienware m15 R7
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Dig into reviews and images
Tom's Hardware
Brandon Hill | October 2022
"The Alienware M15 offers solid gaming and leading endurance. It makes the most of its CPU and GPU while delivering stellar battery life for a gaming laptop. Opening the lid presents a full-size keyboard with honeycomb cutouts above it on the deck. An oblong RBG lightning element surrounds the entire rear panel and can be color-synced with the other lights on the laptop. There’s not a lot to dislike about the M15 Its productivity performance lagged in some areas, particularly in the storage benchmark, and it’s a bit heavy. Alienware has a clear winner here with the M15 based on its strong overall performance and endurance."
Lenovo Legion Slim 5
See more
Dig into reviews and images
PCMag
Mark Knapp | August 2023
"The Lenovo Legion Slim 5 Gen 8 acknowledges that a gaming laptop doesn’t have to be as thick as possible and can still ensure adequate cooling when the muscles need flexing. To this end, in the Slim 5 Gen 8, it finds a neat balance of refined, trimmed-down design that still lets its internals cruise (even above their max power ratings). Lenovo then added in some high-end build quality with an altogether excellent keyboard that’s useful for both work and play."
Get a great deal on the Dell Alienware m15 R7 or the Lenovo Legion Slim 5
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.
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