Between the UHD35STx and X2-4K, the UHD35STx comes out ahead in brightness, while the X2-4K wins on light source. Overall, the UHD35STx scores 89.1 and the X2-4K scores 78.6 on our Mars Score.
Which should you buy?
The UHD35STx is the clear pick on raw spec strength, leading by 10.5 points on the Mars Score. The margin is wide enough that the underdog only makes sense if its individual strengths line up with what you specifically need.
Pick the UHD35STx if you care most about brightness. The biggest gaps in its favor are brightness.
Pick the X2-4K if you care most about light source. Its strongest claims are light source.
Both ship with comparable resolution, short-throw, so those specs don't separate the two — focus on the differences below.
Bottom line: the UHD35STx is the safer default. The other model is the right choice only when its specific advantages line up with your priorities.
Why Optoma - UHD35STx wins
- ▲Brightness — 24.14% more. 3600 lm vs 2900 lm.
Why ViewSonic - X2-4K wins
- ▲Light source: Laser (vs Lamp).
Spec comparison
Image
| Spec | Optoma - UHD35STx | ViewSonic - X2-4K |
|---|---|---|
| Resolutionⓘ | 4K | 4K |
| Brightness | 3600 lmlead | 2900 lm |
| Contrast | 1000000:1 | 3000000:1 |
| Light source | Lamp | Laserlead |
| Short-throw | true | true |
Smart & Connectivity
| Spec | Optoma - UHD35STx | ViewSonic - X2-4K |
|---|---|---|
| Smart OS | None | Google TV |
| HDMI inputs | 2 | 2 |
| Built-in speakers | true | true |
Frequently asked
Spec-level deep dives
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