Where they actually differ
The most decisive specs, ranked by how much they matter — before the full spec table.
| Spec | LG - C5 OLED 77 | Samsung - QN900F 8K 65 |
|---|---|---|
| Peak brightness | 1300 nits | 3000 nits |
| Screen size | 77 " | 65 " |
| Refresh rate | 144 Hz | 165 Hz |
| Dolby Vision | true | false |
| Panel type | OLED | Mini-LED |
| Smart OS | webOS | Tizen |
Between the C5 OLED 77 and QN900F 8K 65, the C5 OLED 77 comes out ahead in screen size / dolby vision, while the QN900F 8K 65 wins on peak brightness / refresh rate. Overall, the C5 OLED 77 scores 71.5 and the QN900F 8K 65 scores 74.1 on our Mars Score.
Which should you buy?
These two are nearly even on the Mars Score (71.5 vs 74.1). The decision is not about overall quality — both clear the bar — it is about which specific trade-offs fit your use.
Pick the C5 OLED 77 if the display is what you stare at all day — refresh rate, brightness, or sharpness is where the difference will be most visible. The biggest gaps in its favor are screen size, dolby vision, panel type, among others. The single most decisive one: Screen size — 18.46% more. 77 " vs 65 ".
Pick the QN900F 8K 65 if you care most about peak brightness / refresh rate. Its strongest claims are peak brightness, refresh rate. The single most decisive one: Peak brightness — 130.77% more. 3000 nits vs 1300 nits.
Both ship with comparable hdmi 2.1 ports, vrr, so those specs do not separate the two — focus on the differences below.
Bottom line: there is no wrong answer here — match the spec advantages to how you actually use the product. The Mars Score parity says both are well-rounded; the differences are about trade-offs, not quality.
Which should you buy: LG - C5 OLED 77 or Samsung - QN900F 8K 65?
Samsung - QN900F 8K 65 leads the current Mars Score by 2.6 points.The more useful decision is the trade-off behind that result: compare screen size, panel type, refresh rate against the way you will actually use the product.
Choose LG - C5 OLED 77 if…
LG - C5 OLED 77 has the measurable edge on screen size in, has dolby vision, panel type.
Choose Samsung - QN900F 8K 65 if…
Samsung - QN900F 8K 65 has the measurable edge on peak brightness nits, refresh rate hz.
This is a structured comparison of the published catalog values. It is not a claim of identical real-world performance across every workload; use the linked spec drill-downs and methodology page to inspect the inputs.
Why LG - C5 OLED 77 wins
- ▲Screen size — 18.46% more. 77 " vs 65 ".
- ▲Has Dolby Vision.
- ▲Panel type: OLED (vs Mini-LED).
- ▲Smart OS: webOS (vs Tizen).
Why Samsung - QN900F 8K 65 wins
- ▲Peak brightness — 130.77% more. 3000 nits vs 1300 nits.
- ▲Refresh rate — 14.58% more. 165 Hz vs 144 Hz.
Spec comparison
Display
| Spec | LG - C5 OLED 77 | Samsung - QN900F 8K 65 |
|---|---|---|
| Screen size | 77 "lead | 65 " |
| Panel typeⓘ | OLEDlead | Mini-LED |
| Resolutionⓘ | 4K | 8Klead |
| Refresh rateⓘ | 144 Hz | 165 Hzlead |
| Peak brightnessⓘ | 1300 nits | 3000 nitslead |
HDR & Smart
| Spec | LG - C5 OLED 77 | Samsung - QN900F 8K 65 |
|---|---|---|
| Dolby Visionⓘ | truelead | false |
| HDR10+ⓘ | false | truelead |
| Smart OS | webOSlead | Tizen |
| Dolby Atmosⓘ | true | true |
Gaming
| Spec | LG - C5 OLED 77 | Samsung - QN900F 8K 65 |
|---|---|---|
| HDMI 2.1 portsⓘ | 4 | 4 |
| VRRⓘ | true | true |
| ALLM | true | true |
Frequently asked
Which is brighter, C5 OLED 77 or QN900F 8K 65?+
QN900F 8K 65 peaks at 3000 nits vs 1300 nits.
Which is better for gaming, C5 OLED 77 or QN900F 8K 65?+
QN900F 8K 65 offers 165Hz refresh and 4 HDMI 2.1 ports.
Does C5 OLED 77 or QN900F 8K 65 support Dolby Vision?+
C5 OLED 77 supports Dolby Vision; QN900F 8K 65 does not.