Where they actually differ
The most decisive specs, ranked by how much they matter — before the full spec table.
| Spec | LG - UltraGear 45GX950A-B | MSI - MPG 321URX |
|---|---|---|
| Refresh rate | 165 Hz | 240 Hz |
| Screen size | 45 " | 32 " |
| Peak brightness | 1300 nits | 1000 nits |
| USB-C Power Delivery | 90 W | 98 W |
| DCI-P3 coverage | 98.5 % | 99 % |
| Panel type | OLED | QD-OLED |
Between the UltraGear 45GX950A-B and MPG 321URX, the UltraGear 45GX950A-B comes out ahead in screen size / peak brightness, while the MPG 321URX wins on refresh rate / usb-c power delivery. Overall, the UltraGear 45GX950A-B scores 81.4 and the MPG 321URX scores 78.2 on our Mars Score.
Which should you buy?
The UltraGear 45GX950A-B edges ahead on the Mars Score (81.4 vs 78.2), but the 3.2-point gap is small enough that the right pick comes down to which spec advantages matter to you.
Pick the UltraGear 45GX950A-B 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, peak brightness. The single most decisive one: Screen size — 40.63% more. 45 " vs 32 ".
Pick the MPG 321URX if you care most about refresh rate / usb-c power delivery. Its strongest claims are refresh rate, usb-c power delivery, dci-p3 coverage, among others. The single most decisive one: Refresh rate — 45.45% more. 240 Hz vs 165 Hz.
Both ship with comparable response time (gtg), g-sync, freesync, 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 - UltraGear 45GX950A-B or MSI - MPG 321URX?
LG - UltraGear 45GX950A-B leads the current Mars Score by 3.2 points.The more useful decision is the trade-off behind that result: compare screen size, refresh rate, panel type against the way you will actually use the product.
Choose LG - UltraGear 45GX950A-B if…
LG - UltraGear 45GX950A-B has the measurable edge on screen size in, peak brightness nits.
Choose MSI - MPG 321URX if…
MSI - MPG 321URX has the measurable edge on refresh rate hz, has usb c pd w, color gamut dci p3 pct.
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 - UltraGear 45GX950A-B wins
- ▲Screen size — 40.63% more. 45 " vs 32 ".
- ▲Peak brightness — 30.00% more. 1300 nits vs 1000 nits.
Why MSI - MPG 321URX wins
- ▲Refresh rate — 45.45% more. 240 Hz vs 165 Hz.
- ▲USB-C Power Delivery — 8.89% more. 98 W vs 90 W.
- ▲DCI-P3 coverage — 0.51% more. 99 % vs 98.5 %.
- ▲Panel type: QD-OLED (vs OLED).
Spec comparison
Panel
| Spec | LG - UltraGear 45GX950A-B | MSI - MPG 321URX |
|---|---|---|
| Screen size | 45 "lead | 32 " |
| Panel typeⓘ | OLED | QD-OLEDlead |
| Resolutionⓘ | 5Klead | 4K |
| Aspect ratioⓘ | 21:9 | 16:9 |
| Curvedⓘ | truelead | false |
Performance
| Spec | LG - UltraGear 45GX950A-B | MSI - MPG 321URX |
|---|---|---|
| Refresh rateⓘ | 165 Hz | 240 Hzlead |
| Response time (GtG)ⓘ | 0.03 ms | 0.03 ms |
| Peak brightnessⓘ | 1300 nitslead | 1000 nits |
| DCI-P3 coverageⓘ | 98.5 % | 99 %lead |
| HDRⓘ | true | true |
| G-Syncⓘ | true | true |
| FreeSyncⓘ | true | true |
Connectivity
| Spec | LG - UltraGear 45GX950A-B | MSI - MPG 321URX |
|---|---|---|
| HDMI ports | 2 | 2 |
| DisplayPort ports | 1 | 1 |
| USB-C inputⓘ | true | true |
| USB-C Power Deliveryⓘ | 90 W | 98 Wlead |
| KVM | true | true |
Frequently asked
Which has higher refresh rate, UltraGear 45GX950A-B or MPG 321URX?+
MPG 321URX refreshes at 240Hz vs 165Hz.
Which has faster response time, UltraGear 45GX950A-B or MPG 321URX?+
MPG 321URX responds in 0.03ms vs 0.03ms.
Does UltraGear 45GX950A-B or MPG 321URX have USB-C with power delivery?+
Both offer USB-C PD — 90W on UltraGear 45GX950A-B, 98W on MPG 321URX.