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Updated January 10, 2024·
Choosing between the ASUS ROG Zephyrus G15 and the Lenovo Legion Slim 5i depends on your priorities. If you value a higher battery capacity and slightly better portability, the ASUS might suit you better; it also offers strong performance for general use, 3D/machine learning, and engineering tasks. However, it can be more expensive and may not be the best for intensive gaming despite being powerful. On the other hand, the Lenovo offers good value with less expense and solid performance for engineering and 3D tasks, along with a better screen aspect ratio. It's heavier than the ASUS, which might affect portability, and it has a smaller battery, potentially reducing time between charges. Both have ample storage, sufficient RAM for demanding tasks, and no touchscreen, but they differ in battery life and graphics processing, so consider what matters most for your usage. 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 ASUS ROG Zephyrus G15
- Very good overall build quality
- Good portability
- Best in class speakers
Advantages of the Lenovo Legion Slim 5i
- Very good for gaming and AI
- Very good overall display quality
- Very good keyboard
Key differences
Screen Quality
7.9
8.0
15.6in
SIZE
16.0in
2560 x 1440
RESOLUTION
2560 x 1600
IPS
DISPLAY TECHNOLOGY
IPS
165Hz
REFRESH RATE
165Hz
309.0 nits
BRIGHTNESS
343.0 nits
The ASUS ROG Zephyrus G15 has a better screen than the Lenovo Legion Slim 5i for engineering and design, while the Lenovo Legion Slim 5i has a better screen for gaming and AI, and content creation.
For general use, the ASUS ROG Zephyrus G15's display offers crisp imagery and pleasing color contrasts due to its high resolution and panel type, ensuring sharp text and vivid pictures, while its superior brightness enhances visibility in various lighting conditions. When it comes to engineering and design, the ASUS has a wide color gamut, displaying more accurate colors critical for detailed work, but its color fidelity is less crucial for the Lenovo Legion Slim 5i's still respectable display. However, both laptops fall short for gaming and 3D applications, as their screens have lower refresh rates, which means less fluid motion and slower response times compared to laptops designed with higher refresh rates specifically for those purposes.
Battery
9.5 Hours
7.0 Hours
The ASUS ROG Zephyrus G15 has 9.5 hours of battery life. The Lenovo Legion Slim 5i 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.
Portability
Good
Fair
15.6in
SIZE
16.0in
4.1 lbs
WEIGHT
5.2 lbs
0.7in
THICKNESS
0.9in
The ASUS ROG Zephyrus G15 has good portability, while the Lenovo Legion Slim 5i has only fair portability.
The most portable laptops are small, thin, and light.
Build Quality
8.5
7.4
The ASUS ROG Zephyrus G15 has very good build quality, while the Lenovo Legion Slim 5i has good build quality.
PerfectRec’s Build Quality Score incorporates case materials, display and keyboard flex, hinge quality, and overall reliability.
Cost
$1,637
$1,055
$500
$1,000
$1,500
$2,000
$2,500
The ASUS ROG Zephyrus G15 has a price of $1,637 and the Lenovo Legion Slim 5i costs $1,055.
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Key similarities
General Use
7.9
7.9
2560 x 1440
RESOLUTION
2560 x 1600
IPS
DISPLAY TECHNOLOGY
IPS
309.0 nits
DISPLAY BRIGHTNESS
343.0 nits
9.5 Hours
BATTERY LIFE
7.0 Hours
6.5/10
KEYBOARD QUALITY SCORE
8.5/10
7.5/10
PORTABILITY SCORE
6.7/10
The Lenovo Legion Slim 5i and ASUS ROG Zephyrus G15 are both good for general use.
PerfectRec’s General Use Score takes into account the many different features of the laptop that make it more or less suitable for general productivity, web browsing, streaming, video calls, and running a wide variety of apps and programs.
Gaming and AI
7.5
8.0
7.4/10
OVERALL GPU SCORE
8.4/10
2560 x 1440
RESOLUTION
2560 x 1600
165Hz
REFRESH RATE
165Hz
Yes
SUPPORTS DLSS
Yes
No
MUX SWITCH / ADVANCED OPTIMUS
Yes
6.5/10
FAN NOISE SCORE
6.5/10
Although they have very similar scores, PerfectRec considers Lenovo Legion Slim 5i to be very good for gaming and AI, while the ASUS ROG Zephyrus G15 is good.
The Lenovo Legion Slim 5i is very good for gaming and 3D partly because it has a more recent Nvidia RTX 4060 GPU, which generally offers better graphics performance over the somewhat older Nvidia RTX 3070 in the ASUS ROG Zephyrus G15, and both have high screen refresh rates that contribute to smoother visuals in fast-paced games. While the ASUS has a commendable setup for gaming and 3D, the Legion Slim 5i's more current hardware may provide an edge in the latest games and applications.
Engineering and Design
8.0
8.4
7.5/10
OVERALL CPU SCORE
9.0/10
7.4/10
OVERALL GPU SCORE
8.4/10
16.0 GB
RAM
16.0 GB
The Lenovo Legion Slim 5i and ASUS ROG Zephyrus G15 are both very good for engineering and design.
The ASUS ROG Zephyrus G15 and the Lenovo Legion Slim 5i are highly suited for engineering and design due to their powerful CPUs and high-quality GPUs which are crucial for demanding applications and graphics-intensive tasks. Both laptops feature sufficient RAM and high-resolution screens with good color coverage and detail clarity, while the Legion Slim 5i offers a slightly taller screen aspect ratio for extra vertical workspace and the ROG Zephyrus G15 maintains an edge with a more color-accurate panel, making each a strong contender depending on specific preferences in display and performance needs.
Content Creation
8.0
8.0
7.5/10
OVERALL CPU SCORE
9.0/10
2560 x 1440
RESOLUTION
2560 x 1600
16.0 GB
RAM
16.0 GB
IPS
DISPLAY TECHNOLOGY
IPS
The ASUS ROG Zephyrus G15 and Lenovo Legion Slim 5i are both very 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
7.4
7.8
7.5/10
OVERALL CPU SCORE
9.0/10
16.0 GB
RAM
16.0 GB
2560 x 1440
RESOLUTION
2560 x 1600
6.5/10
KEYBOARD QUALITY SCORE
8.5/10
The Lenovo Legion Slim 5i and ASUS ROG Zephyrus G15 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.
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How the ASUS ROG Zephyrus G15 and the Lenovo Legion Slim 5i compare to other laptops
Spec Comparison
 |  | |
| ASUS ROG Zephyrus G15 | Lenovo Legion Slim 5i |
GENERAL | |||
|---|---|---|---|
| Price | |||
$1,637 | $1,055 | ||
Release Date | |||
Release Date | May 1, 2021 | May 1, 2023 | |
Overall Dimensions | |||
Overall Dimensions | 14'' x 9.6'' x 0.78'' | 14.2'' x 10.3'' x 0.99'' | |
Weight | |||
Weight | 4.19 lbs | 5.29 lbs | |
Width | |||
Width | 13.98" | 14.16" | |
Depth | |||
Depth | 9.57" | 10.25" | |
INTERNAL | |||
|---|---|---|---|
Processor | |||
Processor | AMD Ryzen 9 5900HS | Intel i7-13700H | |
RAM | |||
RAM | 16 GB | 16 GB | |
DDR Memory Version | |||
DDR Memory Version | 4 | 5 | |
RAM Slots | |||
RAM Slots | 1 | 2 | |
Storage | |||
Storage | 1024 GB | 1024 GB | |
BATTERY | |||
|---|---|---|---|
Battery Life | |||
Battery Life | 9.5 Hours | 7 Hours | |
Battery Capacity | |||
Battery Capacity | 90 Wh | 80 Wh | |
SCREEN | |||
|---|---|---|---|
Diagonal Size | |||
Diagonal Size | 15.6" | 16" | |
Display Technology | |||
Display Technology | IPS | IPS | |
Resolution | |||
Resolution | 2560 x 1440 | 2560 x 1600 | |
Refresh Rate | |||
Refresh Rate | 165Hz | 165Hz | |
Display Brightness | |||
Display Brightness | 309 nits | 343 nits | |
RELIABILITY, APPEARANCE & ACOUSTICS | |||
|---|---|---|---|
Build Quality Score | |||
Build Quality Score | 8.5/10 | 7.4/10 | |
Portability Score | |||
Portability Score | 7.5/10 | 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 | 6.5/10 | 6.5/10 | |
HARDWARE FEATURES | |||
|---|---|---|---|
Keyboard Quality Score | |||
Keyboard Quality Score | 6.5/10 | 8.5/10 | |
Speaker Quality Score | |||
Speaker Quality Score | 9.5/10 | 7/10 | |
Webcam | |||
Webcam | No Webcam | 1080p | |
Fingerprint Reader | |||
Fingerprint Reader | Yes | No | |
Backlit Keyboard | |||
Backlit Keyboard | Yes | Yes | |
Number Pad | |||
Number Pad | No | Yes | |
CONNECTIVITY | |||
|---|---|---|---|
USB Type-A | |||
USB Type-A | 2 | 2 | |
USB-C ports | |||
USB-C ports | 2 | 2 | |
USB-C Charging | |||
USB-C Charging | Yes | Yes | |
Display Outputs | |||
Display Outputs | 3 | 3 | |
Thunderbolt Ports | |||
Thunderbolt Ports | 0 | 0 | |
Shopping
ASUS ROG Zephyrus G15
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Dig into reviews and images
NotebookCheck
Florian Glaser | February 2021
"As long as you're aware of the fact that the GeForce RTX 3080 laptop version can only unfold its potential to a limited extent due to Asus's low TDP setting and that it can be slower than a fast RTX 3070 laptop, the ROG Zephyrus G15 GA503Q cuts a fine figure. One of the biggest highlights turns out to be the WQHD panel, since it attracts customers with 165 Hz, relatively fast response times, FreeSync, and good color-space coverage. Other selling points are the surprisingly rich sound, the long battery life, and the sleek design. In terms of looks, the white edition stands out nicely from the competition."
Lenovo Legion Slim 5i
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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 ASUS ROG Zephyrus G15 or the Lenovo Legion Slim 5i
About ASUS
ASUS, a Taiwanese electronics brand, is one of the largest personal computer vendor by market share. The majority of their laptops are targeted towards personal use or gaming. Their most popular product lines include the budget-friendly VivoBook, more premium ZenBook, and their TUF and ROG gaming laptops, the latter of which has a reputation for excellent gaming performance.
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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