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ASUS ROG Swift PG42UQ 42" vs LG UltraFine 40U990A-W

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

ASUS ROG Swift PG42UQ 42"

41.5" · 3840×2160 · OLED
Optimal Viewing Distance 82cm
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LG UltraFine 40U990A-W

39.7" · 5120×2160 · IPS
Optimal Viewing Distance 62cm
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Category Ranking

Pixel Density (PPI)67in category
ASUS ROG Swift PG42UQ 42"106 PPI #64
LG UltraFine 40U990A-W140 PPI #30
93 PPI224 PPI
HDR Peak Brightness67in category
ASUS ROG Swift PG42UQ 42"1000 nits #7
LG UltraFine 40U990A-W600 nits #22
250 nits2000 nits
DCI-P3 Color Gamut63in category
ASUS ROG Swift PG42UQ 42"98% #31
LG UltraFine 40U990A-W99% #2
79%100%
Refresh Rate
ASUS ROG Swift PG42UQ 42"138 Hz
LG UltraFine 40U990A-W120 Hz
StandardHighUltra

Summary

  • Sharpness: advantage LG UltraFine 40U990A-W — At 65cm, the LG UltraFine 40U990A-W is retina (140 PPI) while the ASUS ROG Swift PG42UQ 42" is not — you need to sit at least 82cm away for pixel-free viewing.
  • Brightness: advantage ASUS ROG Swift PG42UQ 42" — Similar SDR brightness (450 vs 450 nits), but the ASUS ROG Swift PG42UQ 42" leads in HDR peak (1000 vs 600 nits).

Key Differences

Specification ASUS ROG Swift PG42UQ 42" LG UltraFine 40U990A-W
Screen Size 41.5" 39.7"
Refresh Rate 138 Hz 120 Hz
Response Time 0.1 ms GTG 5 ms GTG
HDR Peak Brightness 1000 nits 600 nits
Contrast Ratio 1:1,000,000 1:2,000
Color Gamut sRGB 133% · DCI-P3 98% · Adobe RGB 94% sRGB 100% · DCI-P3 99%
Resolution 3840×2160 5120×2160
Pixel Density (PPI) 106 140
Optimal Viewing Distance 82cm 62cm
Year 2022 2025
All specifications
Specification ASUS ROG Swift PG42UQ 42" 2022 LG UltraFine 40U990A-W 2025
Screen Size 41.5" (Better) 39.7"
Resolution 3840×2160 5120×2160 (Better)
Pixel Density (PPI) 106 140 (Better)
Optimal Viewing Distance 82cm 62cm (Better)
Panel Type OLED IPS
Viewing Angle 178° 178°
Aspect Ratio 16:9 21:9
Refresh Rate 138 Hz (Better) 120 Hz
Variable Refresh Rate (VRR) G-SYNC Compatible FreeSync Premium
Response Time 0.1 ms GTG (Better) 5 ms GTG
HDR Certification None DisplayHDR 600
SDR Brightness 450 nits 450 nits
HDR Peak Brightness 1000 nits (Better) 600 nits
Contrast Ratio 1:1,000,000 (Better) 1:2,000
Ports 4x HDMI · 1x DP · USB Hub 2x HDMI · 1x DP · USB-C · USB Hub
Color Gamut sRGB 133% · DCI-P3 98% · Adobe RGB 94% (Better) sRGB 100% · DCI-P3 99%
Year 2022 2025 (Better)

Frequently Asked Questions

Which has better PPI: ASUS ROG Swift PG42UQ 42" or LG UltraFine 40U990A-W?
The LG UltraFine 40U990A-W has 140 PPI compared to 106 PPI for the ASUS ROG Swift PG42UQ 42".
Which has a closer optimal viewing distance?
The LG UltraFine 40U990A-W requires 62cm vs 82cm for the ASUS ROG Swift PG42UQ 42" 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).

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