The DisplayPort standard defines three different transmission speeds that a DP link can operate at, called HBR, HBR2, and HBR3. (There is also a lower mode called RBR but no one cares about that one)
The basic speed, HBR, is enough for up to 144 Hz at 1080p. Higher resolutions and refresh rates require higher transmission speeds. To operate at a higher speed, the devices on both ends must each support that mode (HBR2 or HBR3), and the DP cable must also be rated to handle that speed.
HBR Speed
HBR speed is 10.8 Gbit/s. This mode was defined in DisplayPort version 1.0.
Nearly all DisplayPort devices support the full speed of this mode. Some exceptions include older generation (2011-era) Intel integrated graphics such as Intel HD 3000, which was limited to around 6.75 Gbit/s over DisplayPort. This is not a concern with modern GPUs.
Any DisplayPort cable should handle HBR speed. Even cheap knock-off cables will be capable of this speed.
This speed is enough for up to:
- 1920 × 1080 @ 144 Hz
- 2560 × 1440 @ 85 Hz
- 3840 × 2160 @ 30 Hz
HBR2 Speed
HBR2 speed is 21.6 Gbit/s. This mode was introduced in DisplayPort version 1.2.
Most DisplayPort 1.2 GPUs are capable of the full HBR2 speed. There are some exceptions however; NVIDIA Kepler graphics cards (GTX 600 and 700 series) are limited to only 75% of the full data rate. Therefore, these graphics cards are limited to 200 Hz at 1080p or 120 Hz at 1440p.
HBR2 speed also requires a DisplayPort cable which is properly rated for this speed. Not all DisplayPort cables will handle HBR2 speed, particularly longer cables (> 3 meters). Look for cables that have a VESA certification for HBR2 speed (21.6 Gbit/s). Sometimes these will also be advertised as "DisplayPort version 1.2 cables", although "versions" are not a technically proper way of classifying cables.
Full HBR2 speed is enough for up to:
- 1920 × 1080 @ 240 Hz
- 2560 × 1440 @ 165 Hz
- 3840 × 2160 @ 75 Hz
HBR3 Speed
HBR3 speed is 32.4 Gbit/s. This mode was introduced in DisplayPort version 1.3.
All DisplayPort 1.3 and 1.4 GPUs so far support full HBR3 speed.
HBR3 speed also requires a DisplayPort cable which is properly rated for this speed. Not all DisplayPort cables will handle HBR3 speed. Look for cables that have a VESA certification for HBR3 speed (32.4 Gbit/s), also known as a "DP8K" certification. Sometimes these will also be advertised as "DisplayPort 1.3 cables" or "DisplayPort 1.4 cables", although "versions" are not a technically proper way of classifying cables.
Full HBR3 speed is enough for up to:
- 2560 × 1440 @ 240 Hz
- 3840 × 2160 @ 120 Hz
There are no further speeds at this time. DisplayPort version 1.4 uses the same transmission speed (HBR3) as version 1.3.