Skip to content

ASUS ROG Strix XG309CM vs ASUS ROG Swift OLED PG27UCDM 27"

Side-by-side comparison of viewing distance, PPI, and specifications

ASUS ROG Strix XG309CM

29.5" · 2560×1080 · IPS
Optimal Viewing Distance 93cm
Open in calculator →

ASUS ROG Swift OLED PG27UCDM 27"

26.5" · 3840×2160 · QD-OLED
Optimal Viewing Distance 53cm
Open in calculator →

Category Ranking

Pixel Density (PPI)67in category
ASUS ROG Strix XG309CM94 PPI #65
ASUS ROG Swift OLED PG27UCDM 27"166 PPI #16
93 PPI224 PPI
HDR Peak Brightness67in category
ASUS ROG Strix XG309CM300 nits #65
ASUS ROG Swift OLED PG27UCDM 27"1000 nits #7
250 nits2000 nits
DCI-P3 Color Gamut
ASUS ROG Swift OLED PG27UCDM 27"99% #2
79%100%
Refresh Rate
ASUS ROG Strix XG309CM220 Hz
ASUS ROG Swift OLED PG27UCDM 27"240 Hz
StandardHighUltra

Summary

  • Sharpness: advantage ASUS ROG Swift OLED PG27UCDM 27" — At 65cm, the ASUS ROG Swift OLED PG27UCDM 27" is retina (166 PPI) while the ASUS ROG Strix XG309CM is not — you need to sit at least 93cm away for pixel-free viewing.
  • Brightness: advantage ASUS ROG Strix XG309CM — The ASUS ROG Strix XG309CM is 20% brighter in SDR (300 vs 250 nits), a noticeable difference for outdoor readability. HDR peak: 300 vs 1000 nits.

Key Differences

Specification ASUS ROG Strix XG309CM ASUS ROG Swift OLED PG27UCDM 27"
Screen Size 29.5" 26.5"
SDR Brightness 300 nits 250 nits
Resolution 2560×1080 3840×2160
Pixel Density (PPI) 94 166
Optimal Viewing Distance 93cm 53cm
Refresh Rate 220 Hz 240 Hz
Response Time 1 ms GTG 0.0 ms GTG
HDR Peak Brightness 300 nits 1000 nits
Contrast Ratio 1:1,000 1:1,500,000
USB-C Power Delivery 15 W 90 W
Color Gamut sRGB 110% sRGB 145% · DCI-P3 99% · Adobe RGB 94%
Year 2022 2025
All specifications
Specification ASUS ROG Strix XG309CM 2022 ASUS ROG Swift OLED PG27UCDM 27" 2025
Screen Size 29.5" (Better) 26.5"
Resolution 2560×1080 3840×2160 (Better)
Pixel Density (PPI) 94 166 (Better)
Optimal Viewing Distance 93cm 53cm (Better)
Panel Type IPS QD-OLED
Viewing Angle 178° 178°
Aspect Ratio 21:9 16:9
Refresh Rate 220 Hz 240 Hz (Better)
Variable Refresh Rate (VRR) FreeSync Premium FreeSync Premium Pro
Response Time 1 ms GTG 0.0 ms GTG (Better)
HDR Certification None DisplayHDR True Black 400
SDR Brightness 300 nits (Better) 250 nits
HDR Peak Brightness 300 nits 1000 nits (Better)
Contrast Ratio 1:1,000 1:1,500,000 (Better)
Ports 1x HDMI · 1x DP · USB-C · USB Hub 2x HDMI · 1x DP · USB-C · USB Hub
USB-C Power Delivery 15 W 90 W (Better)
Color Gamut sRGB 110% sRGB 145% · DCI-P3 99% · Adobe RGB 94% (Better)
Year 2022 2025 (Better)

Frequently Asked Questions

Which has better PPI: ASUS ROG Strix XG309CM or ASUS ROG Swift OLED PG27UCDM 27"?
The ASUS ROG Swift OLED PG27UCDM 27" has 166 PPI compared to 94 PPI for the ASUS ROG Strix XG309CM.
Which has a closer optimal viewing distance?
The ASUS ROG Swift OLED PG27UCDM 27" requires 53cm vs 93cm for the ASUS ROG Strix XG309CM to reach retina quality.
Methodology & Sources

Formula: Retina distance (cm) = 3438 / PPI. Displayed values are rounded for readability.

Sources: Official manufacturer spec sheets and product pages. Specs are normalized before comparisons.

Comparison winners are calculated metric by metric (higher is better for most specs; lower is better for distance/response time).

Last updated: