Between the Z27k G3 4K USB-C and ROG Swift PG34WCDM, the Z27k G3 4K USB-C comes out ahead in usb-c power delivery, while the ROG Swift PG34WCDM wins on refresh rate / peak brightness. Overall, the Z27k G3 4K USB-C scores 59 and the ROG Swift PG34WCDM scores 75.1 on our Mars Score.
Which should you buy?
The ROG Swift PG34WCDM is the clear pick on raw spec strength, leading by 16.1 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 Z27k G3 4K USB-C if you care most about usb-c power delivery. The biggest gaps in its favor are usb-c power delivery.
Pick the ROG Swift PG34WCDM if the display is what you stare at all day — refresh rate, brightness, or sharpness is where the difference will be most visible. Its strongest claims are refresh rate, peak brightness, response time (gtg), among others.
There are no meaningful ties on the headline specs — every popular-comparison metric has a winner.
Bottom line: the ROG Swift PG34WCDM is the safer default. The other model is the right choice only when its specific advantages line up with your priorities.
Why HP - Z27k G3 4K USB-C wins
- ▲USB-C Power Delivery — 11.11% more. 100 W vs 90 W.
Why ASUS - ROG Swift PG34WCDM wins
- ▲Refresh rate — 300.00% more. 240 Hz vs 60 Hz.
- ▲Peak brightness — 225.00% more. 1300 nits vs 400 nits.
- ▲Response time (GtG) — 99.40% less. 0.03 ms vs 5 ms.
- ▲Screen size — 25.93% more. 34 " vs 27 ".
- ▲DCI-P3 coverage — 1.02% more. 99 % vs 98 %.
- ▲Has G-Sync.
- ▲Has FreeSync.
- ▲Panel type: QD-OLED (vs IPS).
Spec comparison
Panel
| Spec | HP - Z27k G3 4K USB-C | ASUS - ROG Swift PG34WCDM |
|---|---|---|
| Screen sizeⓘ | 27 " | 34 "lead |
| Panel typeⓘ | IPS | QD-OLEDlead |
| Resolutionⓘ | 4Klead | 1440p |
| Aspect ratioⓘ | 16:9 | 21:9 |
| Curvedⓘ | false | truelead |
Performance
| Spec | HP - Z27k G3 4K USB-C | ASUS - ROG Swift PG34WCDM |
|---|---|---|
| Refresh rateⓘ | 60 Hz | 240 Hzlead |
| Response time (GtG)ⓘ | 5 ms | 0.03 mslead |
| Peak brightnessⓘ | 400 nits | 1300 nitslead |
| DCI-P3 coverageⓘ | 98 % | 99 %lead |
| HDRⓘ | true | true |
| G-Syncⓘ | false | truelead |
| FreeSyncⓘ | false | truelead |
Connectivity
| Spec | HP - Z27k G3 4K USB-C | ASUS - ROG Swift PG34WCDM |
|---|---|---|
| HDMI ports | 1 | 2lead |
| DisplayPort ports | 1 | 1 |
| USB-C input | true | true |
| USB-C Power Deliveryⓘ | 100 Wlead | 90 W |
| KVM | true | true |
Frequently asked
Which has higher refresh rate, Z27k G3 4K USB-C or ROG Swift PG34WCDM?+
ROG Swift PG34WCDM refreshes at 240Hz vs 60Hz.
Which has faster response time, Z27k G3 4K USB-C or ROG Swift PG34WCDM?+
ROG Swift PG34WCDM responds in 0.03ms vs 5ms.
Does Z27k G3 4K USB-C or ROG Swift PG34WCDM have USB-C with power delivery?+
Both offer USB-C PD — 100W on Z27k G3 4K USB-C, 90W on ROG Swift PG34WCDM.
Spec-level deep dives
More from the same brands
vsMars is reader-supported. When you buy through links on our site, we may earn an affiliate commission at no extra cost to you. Learn more.