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Updated January 10, 2024·
When deciding between the ASUS ROG Zephyrus G15 and the Lenovo Slim Pro 9i, consider your priorities. The ASUS offers robust gaming performance and a large screen, which is great for gaming and engineering tasks, but it's less portable and has a shorter battery life. In contrast, the Lenovo has a smaller, sharper touch screen with more vivid colors and longer battery life, making it better for general use and portability. Additionally, it has superior speakers, webcam, and keyboard quality. Both have similar storage and price, but the Lenovo includes twice the RAM, which can enhance multitasking and complex tasks. 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
- Best in class speakers
Advantages of the Lenovo Slim Pro 9i
- Very good for general use
- Very good for software development
- Best in class overall display quality
- Very good keyboard
Key differences
General Use
7.9
8.5
2560 x 1440
RESOLUTION
3072 x 1920
IPS
DISPLAY TECHNOLOGY
Mini LED
309.0 nits
DISPLAY BRIGHTNESS
618.0 nits
9.5 Hours
BATTERY LIFE
6.0 Hours
6.5/10
KEYBOARD QUALITY SCORE
8.0/10
7.5/10
PORTABILITY SCORE
7.6/10
The Lenovo Slim Pro 9i is very good for general use, while the ASUS ROG Zephyrus G15 is good.
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.
Engineering and Design
8.0
8.9
7.5/10
OVERALL CPU SCORE
9.0/10
7.4/10
OVERALL GPU SCORE
6.9/10
16.0 GB
RAM
32.0 GB
The Lenovo Slim Pro 9i and ASUS ROG Zephyrus G15 are both very good for engineering and design, though the Lenovo Slim Pro 9i is somewhat better.
The ASUS ROG Zephyrus G15 offers a potent AMD Ryzen processor and Nvidia RTX GPU, suitable for engineering tasks, with a good quality IPS screen, but it comes with less RAM compared to the Lenovo Slim Pro 9i, which boasts a higher amount of RAM, a more recent Intel processor, Nvidia RTX GPU, and a superior Mini LED touchscreen with higher resolution and brightness, enhancing screen quality significantly for design work.
Software Development
7.4
8.3
7.5/10
OVERALL CPU SCORE
9.0/10
16.0 GB
RAM
32.0 GB
2560 x 1440
RESOLUTION
3072 x 1920
6.5/10
KEYBOARD QUALITY SCORE
8.0/10
The Lenovo Slim Pro 9i is very good for software development, while the ASUS ROG Zephyrus G15 is good.
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
7.9
9.6
15.6in
SIZE
14.5in
2560 x 1440
RESOLUTION
3072 x 1920
IPS
DISPLAY TECHNOLOGY
Mini LED
165Hz
REFRESH RATE
165Hz
309.0 nits
BRIGHTNESS
618.0 nits
The Lenovo Slim Pro 9i has a better screen than the ASUS ROG Zephyrus G15 for general use, gaming and AI, engineering and design, content creation, and software development.
If you prioritize a vibrant and sharp display for everyday tasks like browsing and video streaming, the Lenovo Slim Pro 9i excels with its high resolution and impressive brightness, offering a crisp and vivid visual experience. For professionals in engineering and design, the inclusion of broad color gamuts ensures the Lenovo reproduces colors more accurately, making it ideal for precision work that demands color fidelity. However, for gaming and 3D applications where the action is fast-paced, the ASUS ROG Zephyrus G15, despite its lower image quality in this context, would benefit from a higher refresh rate which is key for a smoother visual experience in these scenarios.
Battery
9.5 Hours
6.0 Hours
The ASUS ROG Zephyrus G15 has 9.5 hours of battery life. The Lenovo Slim Pro 9i has 6 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.
Cost
$1,282
$1,500
$500
$1,000
$1,500
$2,000
$2,500
The ASUS ROG Zephyrus G15 has a price of $1,282 and the Lenovo Slim Pro 9i costs $1,500.
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Key similarities
Gaming and AI
7.5
7.6
7.4/10
OVERALL GPU SCORE
6.9/10
2560 x 1440
RESOLUTION
3072 x 1920
165Hz
REFRESH RATE
165Hz
Yes
SUPPORTS DLSS
Yes
No
MUX SWITCH / ADVANCED OPTIMUS
No
6.5/10
FAN NOISE SCORE
8.0/10
The Lenovo Slim Pro 9i and ASUS ROG Zephyrus G15 are both good for gaming and AI.
The ASUS ROG Zephyrus G15 is equipped with a Nvidia RTX 3070 graphics card and boasts a screen refresh rate of 165 Hz, while the Lenovo Slim Pro 9i has a newer Nvidia RTX 4050 GPU and also offers a high refresh rate of 165 Hz, ensuring smooth visuals for gaming and 3D applications. The Zephyrus has an IPS display, suitable for gaming due to its response times, while the Slim Pro 9i features a Mini LED screen with higher resolution and touch capability, enhancing screen quality for various multimedia experiences.
Content Creation
8.0
8.5
7.5/10
OVERALL CPU SCORE
9.0/10
2560 x 1440
RESOLUTION
3072 x 1920
16.0 GB
RAM
32.0 GB
IPS
DISPLAY TECHNOLOGY
Mini LED
The Lenovo Slim Pro 9i and ASUS ROG Zephyrus G15 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.
Portability
Good
Good
15.6in
SIZE
14.5in
4.1 lbs
WEIGHT
3.7 lbs
0.7in
THICKNESS
0.8in
The Lenovo Slim Pro 9i and ASUS ROG Zephyrus G15 both have good portability.
The most portable laptops are small, thin, and light.
Build Quality
8.5
8.0
The ASUS ROG Zephyrus G15 and Lenovo Slim Pro 9i both have very good build quality.
PerfectRec’s Build Quality Score incorporates case materials, display and keyboard flex, hinge quality, and overall reliability.
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How the ASUS ROG Zephyrus G15 and the Lenovo Slim Pro 9i compare to other laptops
Spec Comparison
 |  | |
| ASUS ROG Zephyrus G15 | Lenovo Slim Pro 9i |
GENERAL | |||
|---|---|---|---|
| Price | |||
$1,282 | $1,500 | ||
Release Date | |||
Release Date | May 1, 2021 | February 1, 2023 | |
Overall Dimensions | |||
Overall Dimensions | 14'' x 9.6'' x 0.78'' | 12.9'' x 9.6'' x 0.85'' | |
Weight | |||
Weight | 4.19 lbs | 3.7 lbs | |
Width | |||
Width | 13.98" | 12.9" | |
Depth | |||
Depth | 9.57" | 9.64" | |
INTERNAL | |||
|---|---|---|---|
Processor | |||
Processor | AMD Ryzen 9 5900HS | Intel i7-13705H | |
RAM | |||
RAM | 16 GB | 32 GB | |
DDR Memory Version | |||
DDR Memory Version | 4 | 5 | |
RAM Slots | |||
RAM Slots | 1 | 0 | |
Storage | |||
Storage | 1024 GB | 1024 GB | |
BATTERY | |||
|---|---|---|---|
Battery Life | |||
Battery Life | 9.5 Hours | 6 Hours | |
Battery Capacity | |||
Battery Capacity | 90 Wh | 75 Wh | |
SCREEN | |||
|---|---|---|---|
Diagonal Size | |||
Diagonal Size | 15.6" | 14.5" | |
Display Technology | |||
Display Technology | IPS | Mini LED | |
Resolution | |||
Resolution | 2560 x 1440 | 3072 x 1920 | |
Refresh Rate | |||
Refresh Rate | 165Hz | 165Hz | |
Display Brightness | |||
Display Brightness | 309 nits | 618 nits | |
RELIABILITY, APPEARANCE & ACOUSTICS | |||
|---|---|---|---|
Build Quality Score | |||
Build Quality Score | 8.5/10 | 8/10 | |
Portability Score | |||
Portability Score | 7.5/10 | 7.7/10 | |
Gaming Laptop Appearance | |||
Gaming Laptop Appearance | Yes | No | |
Premium Business Laptop | |||
Premium Business Laptop | No | No | |
Fan Noise Score | |||
Fan Noise Score | 6.5/10 | 8/10 | |
HARDWARE FEATURES | |||
|---|---|---|---|
Keyboard Quality Score | |||
Keyboard Quality Score | 6.5/10 | 8/10 | |
Speaker Quality Score | |||
Speaker Quality Score | 9.5/10 | 8/10 | |
Webcam | |||
Webcam | No Webcam | 1080p | |
Fingerprint Reader | |||
Fingerprint Reader | Yes | No | |
Backlit Keyboard | |||
Backlit Keyboard | Yes | Yes | |
Number Pad | |||
Number Pad | No | No | |
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 Version | |||
Thunderbolt Version | N/A | 4 | |
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 Slim Pro 9i
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Dig into reviews and images
PCWorld
Matthew S. Smith | August 2023
"The Lenovo Slim Pro 9i is an impressive laptop with a brilliant Mini-LED display, a powerful 100-watt version of Nvidia RTX 4050 graphics, and excellent connectivity. Having run the Cinebench benchmark again, we were impressed with the CPU performance. That makes the Slim Pro 9i is an easy recommendation, especially for those who care about GPU and CPU performance. It’s also a fantastic choice if you frequently view HDR movies and games on your laptop."
Get a great deal on the ASUS ROG Zephyrus G15 or the Lenovo Slim Pro 9i
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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