LG UltraFine 40U990A-W vs Samsung Odyssey G9 49"
Side-by-side comparison of viewing distance, PPI, and specifications
Category Ranking
Pixel Density (PPI)67in category
LG UltraFine 40U990A-W140 PPI #30
Samsung Odyssey G9 49"109 PPI #55
93 PPI224 PPI
HDR Peak Brightness67in category
LG UltraFine 40U990A-W600 nits #22
Samsung Odyssey G9 49"1000 nits #7
250 nits2000 nits
DCI-P3 Color Gamut63in category
LG UltraFine 40U990A-W99% #2
Samsung Odyssey G9 49"95% #48
79%100%
Refresh Rate
LG UltraFine 40U990A-W120 Hz
Samsung Odyssey G9 49"240 Hz
StandardHighUltra
Summary
- Sharpness: advantage LG UltraFine 40U990A-W — At 65cm, the LG UltraFine 40U990A-W is retina (140 PPI) while the Samsung Odyssey G9 49" is not — you need to sit at least 80cm away for pixel-free viewing.
- Brightness: advantage Samsung Odyssey G9 49" — Similar SDR brightness (450 vs 420 nits), but the Samsung Odyssey G9 49" leads in HDR peak (1000 vs 600 nits).
Key Differences
| Specification | LG UltraFine 40U990A-W | Samsung Odyssey G9 49" |
|---|---|---|
| Resolution | 5120×2160 | 5120×1440 |
| Pixel Density (PPI) | 140 | 109 |
| Optimal Viewing Distance | 62cm | 80cm |
| SDR Brightness | 450 nits | 420 nits |
| Year | 2025 | 2020 |
| Screen Size | 39.7" | 48.7" |
| Refresh Rate | 120 Hz | 240 Hz |
| Response Time | 5 ms GTG | 1 ms GTG |
| HDR Peak Brightness | 600 nits | 1000 nits |
| Contrast Ratio | 1:2,000 | 1:2,500 |
| Color Gamut | sRGB 100% · DCI-P3 99% | sRGB 125% · DCI-P3 95% · Adobe RGB 92% |
All specifications
| Specification | LG UltraFine 40U990A-W 2025 | Samsung Odyssey G9 49" 2020 |
|---|---|---|
| Screen Size | 39.7" | 48.7" (Better) |
| Resolution | 5120×2160 (Better) | 5120×1440 |
| Pixel Density (PPI) | 140 (Better) | 109 |
| Optimal Viewing Distance | 62cm (Better) | 80cm |
| Panel Type | IPS | VA |
| Viewing Angle | 178° | 178° |
| Aspect Ratio | 21:9 | 32:9 |
| Refresh Rate | 120 Hz | 240 Hz (Better) |
| Variable Refresh Rate (VRR) | FreeSync Premium | FreeSync Premium Pro |
| Response Time | 5 ms GTG | 1 ms GTG (Better) |
| HDR Certification | DisplayHDR 600 | DisplayHDR 1000 |
| SDR Brightness | 450 nits (Better) | 420 nits |
| HDR Peak Brightness | 600 nits | 1000 nits (Better) |
| Contrast Ratio | 1:2,000 | 1:2,500 (Better) |
| Ports | 2x HDMI · 1x DP · USB-C · USB Hub | 1x HDMI · 2x DP · USB Hub |
| Color Gamut | sRGB 100% · DCI-P3 99% | sRGB 125% · DCI-P3 95% · Adobe RGB 92% (Better) |
| Year | 2025 (Better) | 2020 |
Frequently Asked Questions
Which has better PPI: LG UltraFine 40U990A-W or Samsung Odyssey G9 49"?
The LG UltraFine 40U990A-W has 140 PPI compared to 109 PPI for the Samsung Odyssey G9 49".
Which has a closer optimal viewing distance?
The LG UltraFine 40U990A-W requires 62cm vs 80cm for the Samsung Odyssey G9 49" to reach retina quality.
Related Comparisons
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vs LG UltraFine 40U990A-W 2025 · 140 PPI · 39.7" · 120 Hz
Alienware AW2725DF 27" 2024 · 110 PPI · 26.7" · 360 Hz
vs Samsung Odyssey G9 49" 2020 · 109 PPI · 48.7" · 240 Hz
Alienware AW3225QF 32" 2024 · 139 PPI · 31.6" · 240 Hz
vs LG UltraFine 40U990A-W 2025 · 140 PPI · 39.7" · 120 Hz
Alienware AW3225QF 32" 2024 · 139 PPI · 31.6" · 240 Hz
vs Samsung Odyssey G9 49" 2020 · 109 PPI · 48.7" · 240 Hz
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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