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We've recently released Test Bench 2.0 for Monitors! Read our new VRR Flicker R&D Article and Pursuit Photo R&D Article to learn more.

Dell Alienware AW2521H Monitor Review

Tested using Methodology v1.2
Reviewed Dec 04, 2020 at 10:16 am
Latest change: Writing modified Apr 18, 2023 at 02:27 pm
Dell Alienware AW2521H Picture
7.6
Mixed Usage
7.7
Office
8.3
Gaming
7.2
Media Consumption
7.7
Media Creation
6.3
HDR

The Dell Alienware AW2521H is an excellent gaming monitor. It's one of the first few monitors released with an extremely high 360Hz refresh rate, which helps deliver an incredible response time with silky smooth motion. It also has an exceptionally low input lag and native G-SYNC variable refresh rate (VRR) support, but it doesn't support FreeSync. It's really well-built and offers great ergonomics, so you shouldn't have any difficulty placing it in an ideal viewing position. It has an IPS panel with wide viewing angles, but that comes at the cost of a low contrast ratio, so blacks appear closer to gray when viewed in the dark. The smaller screen and 1080p resolution may be too limiting for office use, but the lower resolution isn't too taxing on your graphics card when gaming.

Our Verdict

7.6 Mixed Usage

The Dell Alienware AW2521H is great overall. It's excellent for gaming thanks to its extremely high 360Hz refresh rate, G-SYNC support, exceptionally low input lag, and incredible response time. It's good for office use because it has great ergonomics and wide viewing angles, but the 1080p resolution may be too limiting for some. It has a decent HDR peak brightness, but it doesn't display a wide color gamut and has a low contrast ratio, so blacks appear gray.

Pros
  • Wide viewing angles.
  • 360Hz refresh rate.
  • Exceptionally low input lag.
  • Incredible response time.
Cons
  • Limiting resolution and size.
  • Low contrast ratio.
7.7 Office

The Dell Alienware AW2521H is good for office use. It has great ergonomics and wide viewing angles, making it easy to share your screen with others around you. It gets bright enough to combat glare in well-lit rooms, and it has good reflection handling. However, the 25 inch screen and 1080p resolution may be too limiting for multitasking.

Pros
  • Wide viewing angles.
  • Great ergonomics.
  • Performs well in bright environments.
Cons
  • Limiting resolution and size.
  • Text can appear a bit blurry.
8.3 Gaming

The Dell Alienware AW2521H is excellent for gaming. It has an extremely high 360Hz refresh rate with an incredible response time, resulting in smooth motion. Input lag is exceptionally low and it has native G-SYNC support. Its IPS panel has a low contrast ratio, so it's not ideal for dark-room gaming, but it has wide viewing angles if you want to share your screen with someone else.

Pros
  • 360Hz refresh rate.
  • Exceptionally low input lag.
  • Incredible response time.
  • Native G-SYNC support.
Cons
  • Low contrast ratio.
7.2 Media Consumption

The Dell Alienware AW2521H is good for consuming media. It has wide viewing angles, so you can easily watch your favorite videos with a few friends. However, the 1080p resolution may be too low for some people. Also, it has a low contrast ratio, so blacks appear closer to gray when viewed in the dark.

Pros
  • Wide viewing angles.
  • Performs well in bright environments.
  • Exceptionally low input lag.
Cons
  • Limiting resolution and size.
  • Low contrast ratio.
7.7 Media Creation

The Dell Alienware AW2521H is very good for content creators. It has great ergonomics and wide viewing angles, making it easy to share your screen with a coworker or client. It performs well in bright rooms thanks to its impressive peak brightness and good reflection handling. However, the 1080p resolution and 25 inch screen isn't ideal if you work with multiple windows opened side-by-side.

Pros
  • Wide viewing angles.
  • Great ergonomics.
  • Exceptional gradient handling.
Cons
  • Limiting resolution and size.
  • Low contrast ratio.
6.3 HDR

Pros
  • Exceptional gradient handling.
  • Decent HDR peak brightness.
Cons
  • Low contrast ratio.
  • Can't display wide color gamut.
  • No local dimming.
  • 7.6 Mixed Usage
  • 7.7 Office
  • 8.3 Gaming
  • 7.2 Media Consumption
  • 7.7 Media Creation
  • 6.3 HDR
  1. Updated Apr 18, 2023: Added that the new Dell Alienware AW2524H is another G-SYNC monitor with an even higher 500Hz Refresh Rate.
  2. Updated Nov 02, 2022: We reviewed the Dell Alienware AW2523HF, which is a similar monitor, and added a note in the Variable Refresh Rate section that the AW2523HF supports FreeSync natively.
  3. Updated Jul 06, 2022: Updated to Test Bench 1.2, resulting in changes to the results and scores with the Response Time and Input Lag. Added tests for Console Compatibility and macOS compatibility and made minor changes to other tests, which you can see in our Changelog.
  4. Updated Jan 12, 2022: Remeasured the SDR color gamut and volume at a 60Hz refresh rate.
  5. Updated Jan 07, 2022: Checked to see if FreeSync works with a newer AMD GPU.
  6. Updated Aug 20, 2021: We corrected a mistake in the measured diagonal of the screen.
  7. Updated Dec 04, 2020: Review published.
  8. Updated Nov 30, 2020: Early access published.
  9. Updated Nov 25, 2020: Our testers have started testing this product.
  10. Updated Nov 25, 2020: The product has arrived in our lab, and our testers will start evaluating it soon.
  11. Updated Oct 14, 2020: We've purchased the product and are waiting for it to arrive in our lab.

Differences Between Sizes And Variants

We tested the Dell Alienware AW2521H, and there are no other variants. However, there are many monitors in the Dell Alienware lineup with various configurations, some of which you can see in the table below.

 Model  Size Panel Resolution Max Refresh Rate VRR HDR Body Color
AW2518HF 25" TN 1080p 240Hz FreeSync  No Silver
AW2521H 24.5" IPS 1080p 360Hz G-SYNC Yes Black
AW2521HF 25" IPS 1080p 240Hz FreeSync and G-SYNC No Black
AW2521HFL 25" IPS 1080p 240Hz FreeSync and G-SYNC No White
AW2720HF 27" IPS 1080p 240Hz FreeSync and G-SYNC No  White
AW2721D 27" IPS 1440p 240Hz G-SYNC Yes White

If someone comes across a different type of panel or if their Dell Alienware AW2521H doesn't correspond to our review, let us know and we'll update the review. Note that some tests, such as the gray uniformity, may vary between individual units.

Our unit of the AW2521H was manufactured in October 2020 and you can see the label here.

Compared To Other Monitors

The Dell Alienware AW2521H is a great 360Hz monitor and very similar to the ASUS ROG Swift 360Hz PG259QN and the MSI Oculux NXG253R. It has an incredible response time and exceptionally low input lag. However, most gamers won't notice the difference between 360Hz and 240Hz panels, which you can get for less, such as the Dell Alienware AW2521HF, or the 280Hz ASUS TUF Gaming VG259QM. Also see our recommendations for the best gaming monitors, the best monitors for PS5/PS5 Pro, and the best monitors for Xbox Series X.

Dell Alienware AW2523HF

The Dell Alienware AW2523HF and the Dell Alienware AW2521H are both great 360Hz gaming monitors with a few differences. The AW2521H has native G-SYNC support, while the AW2523HF has native FreeSync support. It gives you a few extra features if you have an NVIDIA graphics card, like NVIDIA's Reflex Latency Analyzer to measure the latency of your entire setup, and the FreeSync support on the AW2523HF is beneficial if you have an AMD graphics card. On the other hand, the AW2523HF is better for console gaming because it has a Console Mode that downscales 4k images, which the AW2521H doesn't have.

BenQ ZOWIE XL2546K

The Dell Alienware AW2521H is better than the BenQ ZOWIE XL2546K. The Dell has a higher refresh rate of 360Hz and a slightly better response time, resulting in smoother motion and greater responsiveness. It also has a better contrast ratio, wider viewing angles, and gets brighter to combat glare. The Dell has more features, like HDR support and a USB hub with four USB 3.0 ports.

BenQ ZOWIE XL2566K

The Dell Alienware AW2521H is better than the BenQ ZOWIE XL2566K. The Dell has a much better viewing angle, delivering a more consistent visual experience when viewed at an angle. The Dell also supports HDR and gets brighter in SDR to overcome more glare in a bright room. The Dell also natively supports G-SYNC variable refresh rate technology, delivering a tear-free gaming experience with NVIDIA graphics cards.

Dell Alienware AW2521HF

The Dell Alienware AW2521H is better than the Dell Alienware AW2521HF. The AW2521H has a 360Hz refresh rate, supports HDR, has significantly better gradient handling, and has a lower input lag. However, the AW2521HF has much better reflection handling and a wider horizontal viewing angle.

ASUS ROG Swift 360Hz PG259QN

The ASUS ROG Swift 360Hz PG259QN and the Dell Alienware AW2521H are very similar 360Hz monitors. The Dell has a better response time, it gets brighter, and has better ergonomics. However, the ASUS has better reflection handling and better color accuracy.

Dell Alienware AW2524H

The Dell Alienware AW2521H and the Dell Alienware AW2524H are similar gaming monitors with native G-SYNC support. The main difference is that the AW2524H has a higher 500Hz refresh rate than the 360Hz on the AW2521H, and it's also compatible with FreeSync VRR, but their gaming performance is similar otherwise. Other than that, the AW2524H displays a wider range of colors in HDR and has a local dimming feature, which the AW2521H doesn't have, but it performs terribly.

ASUS TUF Gaming VG259QM

The ASUS TUF Gaming VG259QM is slightly better for gaming than the Dell Alienware AW2521H. The ASUS has significantly better ergonomics, a bit better reflection handling, a wider BFI flicker range, and it has built-in speakers. However, the Dell has a higher 360Hz refresh rate, better response time, and slightly lower input lag.

Acer Nitro XV252Q Fbmiiprx

The Acer Nitro XV252Q Fbmiiprx is slightly better for gaming than the Dell Alienware AW2521H. The Acer has a slightly faster refresh rate and slightly better response time, so fast-moving objects are a bit clearer. The Acer also has better reflection handling and better ergonomics. The Dell natively supports NVIDIA's G-SYNC variable refresh rate technology, so it's a bit better than the Acer if you have an NVIDIA graphics card, as it supports NVIDIA's Reflex Latency Analyzer as well as variable overdrive, ensuring a more visually consistent gaming experience.

ViewSonic XG2431

The Dell Alienware AW2521H and the ViewSonic XG2431 are both impressive gaming monitors with a few different features. The Dell is a native G-SYNC monitor with a 360Hz refresh rate, so it's a better choice if you play high-frame-rate games on an NVIDIA graphics card, but FreeSync doesn't work on it. If you need FreeSync, the ViewSonic has native FreeSync support, and G-SYNC also works on it, but it has a lower 240Hz refresh rate.

ASUS ROG Swift 360Hz PG27AQN

The Dell Alienware AW2521H and the ASUS ROG Swift 360Hz PG27AQN are both G-SYNC monitors with a 360Hz refresh rate, and they're both great for gaming. The ASUS does have a slight edge for gaming, mainly because it has better motion handling across its entire refresh rate range. Lastly, the ASUS has a higher 1440p resolution that helps deliver slightly sharper images.

Dell Alienware AW2720HF

The Dell Alienware AW2521H is better than the Dell Alienware AW2720HF. The AW2521H has a much higher 360Hz refresh rate, it gets brighter, supports HDR, has a quicker response time at 60Hz, and has slightly lower input lag. However, the AW2720HF has better ergonomics and better reflection handling.

Dell Alienware AW2721D

The Dell Alienware AW2721D and the Dell Alienware AW2521H are both great monitors that perform similarly in many ways, but they have different resolutions and sizes. The AW2521H is one of the rare monitors with a 360Hz max refresh rate, while the AW2721D has a max refresh rate of 240Hz, but the difference likely won't be noticeable to most gamers. That said, the AW2521H has a slightly better response time with less overshoot and better reflection handling. On the other hand, the AW2721D has a better color gamut and brightness for HDR, and it feels more well-built.

Acer Predator X25 bmiiprzx

The Acer Predator X25 bmiiprzx and the Dell Alienware AW2521H are both excellent gaming monitors geared towards competitive gamers. They both have 360Hz refresh rates and 25 inch 1080p screens, prioritizing motion clarity over resolution. In terms of performance, they are very similar. That said, the Dell has a slightly faster response time at the max 360Hz, although they're about even at 60Hz. If you're looking for a 360Hz monitor, you can't go wrong with either of these, and it may just be a matter of preference.

MSI Oculux NXG253R

The Dell Alienware AW2521H and the MSI Oculux NXG253R are extremely similar overall, but the Dell is slightly better overall. The Dell has a slightly faster response time, it's brighter, and the unit we bought has better accuracy out of the box, but this can vary between units. On the other hand, the MSI has a wider swivel range.

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Video

Test Results

perceptual testing image
Design
Design
Style
Curved
No
Curve Radius
Not Curved

The Dell Alienware AW2521H looks exactly like the Dell Alienware AW2521HF. It has a black body with thin bezels on three sides and a thicker bottom bezel. It has a gamer-oriented design with RGB lighting on the back.

8.5
Design
Build Quality

The Dell Alienware AW2521H has an excellent build quality. It's made entirely out of plastic, and it feels solid throughout. It's well-built, it doesn't wobble, and there aren't any obvious loose parts.

9.0
Design
Ergonomics
Height Adjustment
5.1" (13.0 cm)
Tilt Range
-20° to 5°
Rotate Portrait/Landscape
Yes, Both Ways
Swivel Range
-20° to 20°
Wall Mount
VESA 100x100

The Dell Alienware AW2521H has great ergonomics. Its swivel range is a bit narrow, but you can switch it into portrait mode in either direction. The back of this monitor has a gamer-oriented design with RGB lighting on the stand and the Alienware logo at the top right. There's a hole in the stand for cable management and there's a quick-release button to remove the stand.

Design
Stand
Base Width
18.3" (46.5 cm)
Base Depth
10.3" (26.1 cm)
Thickness (With Display)
8.9" (22.6 cm)
Weight (With Display)
17.0 lbs (7.7 kg)

This monitor has a wide V-shaped stand that takes up a good amount of space. Luckily, there's still room between the legs to place stuff. It supports the screen well and there's minimal wobble.

Design
Display
Size
25"
Housing Width
21.9" (55.7 cm)
Housing Height
13.0" (32.9 cm)
Thickness (Without Stand)
3.3" (8.4 cm)
Weight (Without Stand)
9.9 lbs (4.5 kg)
Borders Size (Bezels)
0.3" (0.7 cm)
Design
Controls

There's a joystick and four buttons on the back of the monitor to control the on-screen display.

Design
In The Box
Power Supply
Internal

  • Power cable
  • DisplayPort cable
  • Mini DisplayPort cable
  • USB to USB-B upstream cable
  • User guide

Picture Quality
6.5
Picture Quality
Contrast
Native Contrast
1,336 : 1
Contrast With Local Dimming
N/A

The Dell Alienware AW2521H has an okay contrast ratio, and it's actually better than most IPS panels. However, blacks still appear closer to gray when viewed in the dark.

0
Picture Quality
Local Dimming
Local Dimming
No
Backlight
Edge

The Dell Alienware AW2521H doesn't have a local dimming feature. The video above is provided for reference only.

8.3
Picture Quality
SDR Brightness
Real Scene
440 cd/m²
Peak 2% Window
435 cd/m²
Peak 10% Window
436 cd/m²
Peak 25% Window
436 cd/m²
Peak 50% Window
437 cd/m²
Peak 100% Window
437 cd/m²
Sustained 2% Window
434 cd/m²
Sustained 10% Window
436 cd/m²
Sustained 25% Window
436 cd/m²
Sustained 50% Window
437 cd/m²
Sustained 100% Window
437 cd/m²
Automatic Brightness Limiting (ABL)
0.000
Minimum Brightness
36 cd/m²

The Dell Alienware AW2521H has impressive peak brightness. It easily gets bright enough to combat glare, and it maintains its brightness very consistent across different content. We measured peak brightness after calibration in the 'Custom Color' Picture Mode with Brightness set to max.

7.1
Picture Quality
HDR Brightness
VESA DisplayHDR Certification
No Certification
Real Scene
457 cd/m²
Peak 2% Window
464 cd/m²
Peak 10% Window
466 cd/m²
Peak 25% Window
466 cd/m²
Peak 50% Window
467 cd/m²
Peak 100% Window
466 cd/m²
Sustained 2% Window
464 cd/m²
Sustained 10% Window
466 cd/m²
Sustained 25% Window
466 cd/m²
Sustained 50% Window
466 cd/m²
Sustained 100% Window
466 cd/m²
Automatic Brightness Limiting (ABL)
0.000

The Dell Alienware AW2521H has decent HDR peak brightness. It gets bright enough to make some highlights stand out in HDR games, but it may not be enough for a satisfying HDR movie experience. Like with its SDR brightness, it's very consistent across different content. We measured peak brightness in the 'Custom Color' Picture Mode, and the Brightness setting automatically locks to '100' when in HDR.

8.0
Picture Quality
Horizontal Viewing Angle
Color Washout From Left
35°
Color Washout From Right
37°
Color Shift From Left
47°
Color Shift From Right
50°
Brightness Loss From Left
38°
Brightness Loss From Right
41°
Black Level Raise From Left
70°
Black Level Raise From Right
70°
Gamma Shift From Left
58°
Gamma Shift From Right
59°

The Dell Alienware AW2521H has a great horizontal viewing angle, which is expected from an IPS panel. The image remains accurate when viewing from the side, so it's ideal for co-op gaming.

7.1
Picture Quality
Vertical Viewing Angle
Color Washout From Below
28°
Color Washout From Above
29°
Color Shift From Below
69°
Color Shift From Above
67°
Brightness Loss From Below
32°
Brightness Loss From Above
33°
Black Level Raise From Below
49°
Black Level Raise From Above
70°
Gamma Shift From Below
28°
Gamma Shift From Above
30°

The Dell Alienware AW2521H has a decent vertical viewing angle. However, you may notice a loss in image accuracy if you mount it above eye-level.

8.0
Picture Quality
Gray Uniformity
50% Std. Dev.
3.463%
50% DSE
0.136%

The gray uniformity is excellent. The edges are a bit darker, but there's minimal dirty screen effect in the center. Uniformity is much better in near-dark scenes.

5.4
Picture Quality
Black Uniformity
Native Std. Dev.
2.390%
Std. Dev. w/ L.D.
N/A

The Dell Alienware AW2521H has poor black uniformity, but this may vary between units. There's severe backlight bleed in the corners and clouding throughout. This can get distracting in dark scenes.

8.7
Picture Quality
Color Accuracy (Pre-Calibration)
Picture Mode
Custom Color
sRGB Gamut Area xy
98.2%
White Balance dE (Avg.)
2.90
Color Temperature (Avg.)
7,005 K
Gamma (Avg.)
2.21
Color dE (Avg.)
1.81
Contrast Setting
75
RGB Settings
100-100-100
Gamma Setting
No Gamma Setting
Brightness Setting
75
Measured Brightness
205 cd/m²
Brightness Locked
No

The Dell Alienware AW2521H has outstanding out-of-the-box accuracy. There are hardly any inaccuracies with white balance and most colors. Gamma follows the target curve well, but some scenes may be too dark. The color temperature is on the cold side, giving the image a blueish tint.

9.6
Picture Quality
Color Accuracy (Post-Calibration)
Picture Mode
Custom Color
sRGB Gamut Area xy
97.6%
White Balance dE (Avg.)
0.52
Color Temperature (Avg.)
6,516 K
Gamma (Avg.)
2.18
Color dE (Avg.)
0.54
Contrast Setting
75
RGB Settings
100-98-90
Gamma Setting
No Gamma Setting
Brightness Setting
30
Measured Brightness
101 cd/m²
ICC Profile
Download

The accuracy after calibration is exceptional. Any remaining inaccuracies can't be spotted without the aid of a colorimeter, and the color temperature is almost spot-on with our 6500K target. The gamma is a bit worse than before calibration, as some scenes are over-brightened, but most people won't notice a difference.

9.0
Picture Quality
SDR Color Gamut
sRGB Coverage xy
98.8%
sRGB Picture Mode
Custom Color
Adobe RGB Coverage xy
73.0%
Adobe RGB Picture Mode
Custom Color

The Dell Alienware AW2521H has an excellent SDR color gamut, almost exactly like the Dell Alienware AW2521HF. It has perfect coverage of the sRGB color space used in most content and decent coverage of the Adobe RGB color space used in photo editing.

9.3
Picture Quality
SDR Color Volume
sRGB In ICtCp
96.8%
sRGB Picture Mode
Custom Color
Adobe RGB In ICtCp
78.0%
Adobe RGB Picture Mode
Custom Color

This monitor has an excellent color volume. It displays bright colors well but struggles with dark colors due to its low contrast ratio.

6.7
Picture Quality
HDR Color Gamut
Wide Color Gamut
No
DCI-P3 Coverage xy
81.3%
DCI-P3 Picture Mode
Custom Color
Rec. 2020 Coverage xy
58.3%
Rec. 2020 Picture Mode
Custom Color

The Dell Alienware AW2521H has an okay HDR color gamut, but it's not considered a wide color gamut for HDR content. It has good coverage of the commonly-used DCI P3 color space, but very limited coverage of the wider Rec. 2020.

7.6
Picture Quality
HDR Color Volume
DCI-P3 In ICtCp
77.5%
DCI-P3 Picture Mode
Custom Color
Rec. 2020 In ICtCp
55.9%
Rec. 2020 Picture Mode
Custom Color

The HDR color volume is okay. It's mainly limited by the monitor's low contrast ratio and lack of a wide color gamut.

7.5
Picture Quality
Reflections
Screen Finish
Matte
Total Reflections
5.8%
Indirect Reflections
4.0%
Calculated Direct Reflections
1.8%

The Dell Alienware AW2521H 's reflection handling is good, but it's not as good as the Dell Alienware AW2521HF. It still performs well in most well-lit environments; however, it may be best to avoid placing it opposite a window.

7.0
Picture Quality
Text Clarity
Pixel Type
IPS
Subpixel Layout
RGB

The text clarity is decent. Enabling ClearType (top photo) helps improve the appearance of diagonal lines, as seen on the R, N, G, and S, but makes straight lines less bold, as seen on the T and I.

9.6
Picture Quality
Gradient
Color Depth
10 Bit

The gradient handling is exceptional. There's minimal banding throughout and you shouldn't notice any banding with real content. It's advertised to have an 8-bit panel, but we can achieve 10-bit in the EDID of the monitor, so it may be 8-bit with FRC, but we don't know for sure.

Motion
9.3
Motion
Refresh Rate
Native Refresh Rate
360 Hz
Max Refresh Rate
360 Hz
Max Refresh Rate Over DP
360 Hz
Max Refresh Rate Over HDMI
240 Hz
Max Refresh Rate Over DP @ 10-bit
300 Hz
Max Refresh Rate Over HDMI @ 10-Bit
144 Hz

The Dell Alienware AW2521H has an incredible refresh rate. You can reach a maximum of 360Hz over a DisplayPort connection and 240Hz over an HDMI connection. However, if you want a native G-SYNC monitor with an even higher 360Hz refresh rate, check out the Dell Alienware AW2524H.

Motion
Variable Refresh Rate (VRR)
FreeSync
No
G-SYNC
Yes (Native)
VRR Maximum
360 Hz
VRR Minimum
< 20 Hz
VRR Supported Connectors
DisplayPort, HDMI
Variable Refresh Rate
Yes

It has native G-SYNC support, but FreeSync doesn't work on it all, and the screen flashes. If you have an AMD graphics card and want FreeSync support, check out the Dell Alienware AW2523HF.

9.2
Motion
Response Time @ Max Refresh Rate
Recommended Overdrive Setting
Fast
Rise / Fall Time
3.1 ms
Total Response Time
6.9 ms
Overshoot Error
0.0%
Worst 3 Rise / Fall Time
5.5 ms
Worst 3 Total Response Time
10.2 ms
Worst 3 Overshoot Error
0.0%

Overdrive SettingResponse Time ChartResponse Time TablesMotion Blur Photo
fastChartTablePhoto
super-fastChartTablePhoto
extremeChartTablePhoto

The Dell Alienware AW2521H has an incredible response time at its max refresh rate of 360Hz. Motion looks exceptionally smooth and you shouldn't notice any motion artifacts. The recommended overdrive setting is 'Fast' as the other settings have too much overshoot. It performs about the same as the other 360Hz monitors we've tested, but is slightly faster than the MSI Oculux NXG253R.

8.9
Motion
Response Time @ 120Hz
Recommended Overdrive Setting
Fast
Rise / Fall Time
3.8 ms
Total Response Time
7.6 ms
Overshoot Error
1.4%
Worst 3 Rise / Fall Time
5.1 ms
Worst 3 Total Response Time
11.5 ms
Worst 3 Overshoot Error
5.5%

Overdrive SettingResponse Time ChartResponse Time TablesMotion Blur Photo
fastChartTablePhoto
super-fastChartTablePhoto
extremeChartTablePhoto

8.0
Motion
Response Time @ 60Hz
Recommended Overdrive Setting
Fast
Rise / Fall Time
4.3 ms
Total Response Time
12.3 ms
Overshoot Error
1.2%
Worst 3 Rise / Fall Time
6.1 ms
Worst 3 Total Response Time
22.1 ms
Worst 3 Overshoot Error
5.1%

Overdrive SettingResponse Time ChartResponse Time TablesMotion Blur Photo
fastChartTablePhoto
super-fastChartTablePhoto
extremeChartTablePhoto

The response time at 60Hz is outstanding, and once again, you shouldn't notice any motion artifacts with fast-moving content. The recommended overdrive setting is 'Fast'; it has a bit of overshoot in lighter transitions, but it's significantly less than the other settings.

Motion
Backlight Strobing (BFI)
Backlight Strobing (BFI)
Yes
Maximum Frequency
240 Hz
Minimum Frequency
144 Hz
Longest Pulse Width Brightness
217 cd/m²
Shortest Pulse Width Brightness
22 cd/m²
Pulse Width Control
Yes
Pulse Phase Control
No
Pulse Amplitude Control
Yes
VRR At The Same Time
No

BFI SettingMotion Blur Photo
pulse-width-100Photo
pulse-width-50Photo
pulse-width-10Photo

This monitor has a backlight strobing feature, commonly known as BFI, to help reduce motion blur. However, it has a narrow flicker range, and you can't use it with VRR enabled.

10
Motion
Image Flicker
Flicker-Free
Yes
PWM Dimming Frequency
0 Hz

The Dell Alienware AW2521H has a flicker-free backlight, which helps reduce eye strain.

Inputs
9.2
Inputs
Input Lag
Native Resolution @ Max Hz
1.7 ms
Native Resolution @ 120Hz
4.8 ms
Native Resolution @ 60Hz
8.4 ms
Backlight Strobing (BFI)
5.5 ms

The Dell Alienware AW2521H has an exceptionally low input lag. It stays low with VRR enabled, which is great for competitive gaming. We measured BFI input lag at its max flicker frequency of 240Hz.

6.7
Inputs
Resolution And Size
Native Resolution
1920 x 1080
Aspect Ratio
16:9
Megapixels
2.1 MP
Pixel Density
91 PPI
Measured Screen Diagonal
24.5"
Screen Area
255 in²

Dell Alienware AW2521H has a decent size and resolution. The 24.5" inch screen size and 1080p resolution may be too limiting for multitasking, but it's great for gaming as the lower resolution helps achieve higher frame rates.

7.0
Inputs
PS5 Compatibility
4k @ 120Hz
No
4k @ 60Hz
No
1440p @ 120Hz
No
1440p @ 60Hz
No
1080p @ 120Hz
Yes
1080p @ 60Hz
Yes
HDR
Yes
VRR
Yes

The Dell Alienware AW2521H has decent compatibility with the PS5. Like all native G-SYNC monitors, it can't display a downscaled 1440p or 4k signal, so you're limited to 1080p. Refresh rates up to 120Hz work, but HDR only works at 60Hz.

4.2
Inputs
Xbox Series X|S Compatibility
4k @ 120Hz
No
4k @ 60Hz
No
1440p @ 120Hz
No
1440p @ 60Hz
No
1080p @ 120Hz
Yes
1080p @ 60Hz
Yes
HDR
No
VRR
Yes

Unfortunately, this monitor can't take full advantage of the Xbox Series S|X. It can't display a downscaled 1440p or 4k signal, and since the Xbox only supports HDR at 4k, this means that this monitor doesn't support HDR at all from the Xbox. 120Hz refresh rates work, but only at 1080p.

Inputs
Inputs Photos
Inputs
Video And Audio Ports
DisplayPort
1 (DP 1.4)
Mini DisplayPort
No
HDMI
2 (HDMI 2.0)
HDMI 2.1 Rated Speed
No HDMI 2.1
DVI
No
VGA
No
Daisy Chaining
No
3.5mm Audio Out
2
HDR10
Yes
3.5mm Audio In
No
3.5mm Microphone In
No

One of the USB inputs can be used for power delivery, so you can charge your mobile devices, but it doesn't work when the monitor is off.

Inputs
USB
USB-A Ports
4
USB-A Rated Speed
5Gbps (USB 3.2 Gen 1)
USB-B Upstream Port
Yes
USB-C Ports
0
USB-C Upstream
No USB-C Ports
USB-C Rated Speed
No USB-C Ports
USB-C Power Delivery
No USB-C Ports
USB-C DisplayPort Alt Mode
No USB-C Ports
Thunderbolt
No
Inputs
macOS Compatibility

The Dell Alienware AW2521H works well with recent MacBooks. HDR works fine, and the variable refresh rate feature works extremely well, with no flickering. Oddly, the refresh rate is capped at 240Hz. Sleep mode works well, and windows return to their original position when the computer wakes up, but like most monitors, they don't return to their original position if you just close the lid on your MacBook.

Features
Features
Additional Features
Speakers
No
RGB Illumination
Controllable
Multiple Input Display
No
KVM Switch
No

The Dell Alienware AW2521H has a few extra features to help improve the user experience.

  • Alien FX RGB Control: Interface used to customize the RGB lighting on the back.
  • NVIDIA Reflex: Helps measure the input lag and reduce it.
  • Timer: Displays a time on the screen.
  • FPS Counter: Displays the current frame rate.
  • Display Alignment: Helps with alignment when setting up multiple monitors.

Features
On-Screen Display (OSD)