Comparison
LK830ST vs GT3900UHD
When you buy through links on Northcourse, we may earn a commission at no additional cost to you. Read the full affiliate disclosure
A side-by-side look at how the BenQ LK830ST and Optoma GT3900UHD compare on specs, accuracy, room requirements, and price. No hype — just the parts of the decision a buyer actually weighs.
Also worth a look
More comparisons with the LK830ST and GT3900UHD
Buy LK830ST
Prices confirmed Nov 10, 2026 · we check every retailer daily
Buy GT3900UHD
Prices confirmed Nov 10, 2026 · we check every retailer daily
When you buy through links on Northcourse, we may earn a commission at no additional cost to you. Read the full affiliate disclosure
Full specificationsEvery spec for both, line by line
Specifications
The numbers, lined up.
Image
| Spec | LK830ST | GT3900UHD |
|---|---|---|
| Resolution | 4K UHD (3840×2160) | 4K UHD (3840×2160) |
| Lumens | 4,000 ANSI | 4,000 (ISO 21118) |
| Picture Mode | Golf picture mode | Golf Mode |
| HDR | — | HDR10, HLG |
| Screen Size | — | 30–150 in (Optoma's page and datasheet) |
- ResolutionLK830ST4K UHD (3840×2160)GT3900UHD4K UHD (3840×2160)
- LumensLK830ST4,000 ANSIGT3900UHD4,000 (ISO 21118)
- Picture ModeLK830STGolf picture modeGT3900UHDGolf Mode
- HDRLK830ST—GT3900UHDHDR10, HLG
- Screen SizeLK830ST—GT3900UHD30–150 in (Optoma's page and datasheet)
Hardware
| Spec | LK830ST | GT3900UHD |
|---|---|---|
| Light Source | Laser (20,000 hours normal, 30,000 eco) | DuraCore laser (30,000 hours, eco) |
| Throw Ratio | 0.496:1 (fixed) | 0.496:1 (fixed) |
| Offset | 114%; no lens shift | 114% (±5%); no lens shift |
| Dimensions | 10.99 × 9.03 × 4.74 in (W × D × H) | 10.8 × 8.5 × 4.5 in (W × D × H, datasheet) |
- Light SourceLK830STLaser (20,000 hours normal, 30,000 eco)GT3900UHDDuraCore laser (30,000 hours, eco)
- Throw RatioLK830ST0.496:1 (fixed)GT3900UHD0.496:1 (fixed)
- OffsetLK830ST114%; no lens shiftGT3900UHD114% (±5%); no lens shift
- DimensionsLK830ST10.99 × 9.03 × 4.74 in (W × D × H)GT3900UHD10.8 × 8.5 × 4.5 in (W × D × H, datasheet)
Requirements
| Spec | LK830ST | GT3900UHD |
|---|---|---|
| Throw Distance | 100 in at about 3.6 ft (BenQ's manual) | 100 in at about 3.6 ft (Optoma's manual) |
- Throw DistanceLK830ST100 in at about 3.6 ft (BenQ's manual)GT3900UHD100 in at about 3.6 ft (Optoma's manual)
Performance
| Spec | LK830ST | GT3900UHD |
|---|---|---|
| Input Lag | 16.7 ms at 4K/60Hz; 8.3 ms at 1080p/120Hz; 4.2 ms at 1080p/240Hz (BenQ) | As low as 4.3 ms at 1080p/240Hz (Optoma) |
- Input LagLK830ST16.7 ms at 4K/60Hz; 8.3 ms at 1080p/120Hz; 4.2 ms at 1080p/240Hz (BenQ)GT3900UHDAs low as 4.3 ms at 1080p/240Hz (Optoma)
Room planner
See each one in your sim room.
The planner draws each unit to scale with your room and your swing: where it mounts, the throw it needs, and whether your shadow crosses the light. Put in your room once, then switch units in the planner to compare.
Persona fitWho each one is better for
Who each one is better for
Honest persona fit, side by side.
Better for GT3900UHD
- Space-Constrained
0.496 puts a 100-inch image up from about 3.6 ft, so it mounts close to the screen and out of the swing, and it does it in 4K. At $1,499 it is the least expensive 4K projector we list.
- Family Setup
4K for movies, low lag for games (4.3 ms at 1080p/240Hz, per Optoma) and a golf picture mode, for $1,499.
- Performance Seeker
4K detail at the tightest throw we list, with published low lag. 4,000 lumens wants some light control; a room with windows is better served by the brighter ZK521ST-B.
Build your simulator in two minutes
Five questions. One tailored build with retailer links.
We ask about your budget, your room, and how you’ll use it. We return a complete build — launch monitor, mat, enclosure, projector, software, PC — with the reasoning behind every pick and the alternatives we considered.