The critical difference between these two 5K2K OLED ultra-wides comes down to how the picture occupies your desk and field of view. Both monitors feature a native 5120 × 2160 resolution at 165 Hz (plus a lower-resolution WFHD mode at 330 Hz). Moving up to the larger 45-inch screen does not buy you a larger desktop in pixel terms.

1. Same Desktop, Different Physical Scale

The size labels hide a practical detail: the specified screen diagonals are 38.86 inches and 44.5 inches, yielding roughly 143 PPI for the 39-inch model and 125 PPI for the 45-inch model.

  • Workspace Parity: At the same operating-system desktop scaling, a document, spreadsheet, or editing workspace displays the exact same number of rows, columns, and application windows on either panel.

  • Physical Scale: On the 45GX950A-B, interface elements and text appear physically larger. This can be desirable if you sit further back or prefer larger game assets, but it does not automatically create extra room for another window.

  • Text & Gaming: For users alternating between text-heavy productivity and gaming, the 39GX950B-B makes sense because it packs the image more tightly without overfilling your workspace.

(Note: Both displays deliver identical pixel counts to your graphics card at native resolution, so choosing the smaller panel does not reduce GPU workload.)

2. Measure Depth as Well as Width

Both displays are nearly a meter wide, making physical layout verification essential before buying:

  • Width Difference: The 45GX950A-B is 991.6 mm wide compared to the 39GX950B-B at 921.4 mm—an increase of 70.2 mm.

  • Depth With Stand: Including their default stands, the 39-inch model is 322.8 mm deep, while the 45-inch model is 342 mm deep (a minor 19.2 mm difference).

  • Depth Without Stand (Panel Thickness): Without the stand, the 39-inch panel depth is 118.7 mm, whereas the 45-inch panel depth jumps to 225.5 mm.

Even if you mount the display on a heavy-duty monitor arm, the 45-inch model's pronounced curve means the screen body itself extends significantly forward. On shallow desks, this can place the screen uncomfortably close to your eyes and crowd your keyboard space.

3. Curvature: 1500R vs. 800R

  • 39GX950B-B (1500R): Features a gentler, more subtle curve that transitions naturally between multi-window productivity and casual gaming.

  • 45GX950A-B (800R): Uses a noticeably tighter 800R radius. Combined with the larger panel size, it offers a deeply immersive, wrapped-around view preferred by dedicated sim-racing or flight-simulator enthusiasts.

Curvature preference is subjective, but a tighter curve requires adequate seating distance to remain comfortable during long working sessions.

4. Shared Performance Modes and Panel Specs

  • Dual Refresh Modes: Both monitors support full-resolution 5120 × 2160 at 165 Hz, as well as a high-speed WFHD mode at 330 Hz (requiring compatible GPU, driver, and cable support).

  • USB-C Power Delivery: Both list up to 90 W USB-C PD, making laptop single-cable connections convenient.

  • Brightness & HDR Ratings:

    • 39GX950B-B: Labelled as 4th-generation Primary RGB Tandem OLED with 335 nits typical brightness and DisplayHDR True Black 500 certification.

    • 45GX950A-B: Rated at 275 nits typical brightness with DisplayHDR True Black 400 certification.

    • (Note: Both monitors utilize WOLED technology architectures; naming conventions describe internal stack structures rather than subpixel layouts or guaranteed longevity.)

Summary: Which Screen Fits Your Setup?

  • Buy the 39GX950B-B if: You want higher pixel density (143 PPI), a gentler curve for mixed work and play, and a shallower screen depth that leaves plenty of desk space for your keyboard and mouse.

  • Buy the 45GX950A-B if: Your primary goal is maximum physical image scale and immersive 800R wrap-around gaming, and you have confirmed that your desk depth can accommodate its deeper curved chassis.