HP ZBook Power G11 via a WD22TB4 docking station

[feherhollo]

I have a HP ZBook Power G11 laptop with an NVIDIA RTX 3000 Ada video card. It comes with a 150W charger.

I would like to use the WD22TB4 docking station with it, which has Power Delivery of

- 130W for "Dell systems" and

- 90W  for non-Dell systems.

My questions

- Would 90W be enough to work with the laptop and charge the battery? (I can't find minimum charging requirements documented for the laptop)

- Why would the charging not be 130W (or more than 90W) if it is using a single Thunderbolt 4 cable? (I thought it was a standard, where delivery is negotiated between the devices)

Thanks!

[resistencia]

Hi @feherhollo 

The dock to function must have the same wattage as the AC charger, in your case it must be at least 150 watts.

[feherhollo]

Thank you for the quick reply, but I am not sure what power and device combinations are you talking about.

The laptop can be charged via the HP power connector or the Thunderbolt 4 port.

- The supplied 150W charger is using the HP power connector.

- Alternatively, the TB4 port also charges the laptop via a 100W charger while in use. (That is 100W power delivery, not 100W charger input.) And that makes sense, as most 3rd party docking stations max out at 100W and HP only is able to achieve more with the combo (HP+USB-C) cable on their 280W G4 dock.

The question is what is the minimum Wattage that it will work with over TB4? Would a 90W charger work for example?

Thanks

[resistencia]

any charger less than 150 watts can only work with the laptop turned off, otherwise it will not charge, That's why HP sells with combined cable.

[feherhollo]

I appreciate the answer, but you are factually wrong about the charging, and your deduction logic is flawed.

My question was not WILL it work, but HOW MANY Watts will work.

If you use a charger with a lower wattage than the laptop's requirement (e.g., 100W for a laptop needing 150W), the laptop might still charge, but it will charge more slowly. If you're running power-hungry tasks while the laptop is on, the charger may not provide enough power to both run the laptop and charge the battery simultaneously, in which case, the laptop might drain power from the battery to make up for the shortfall, or charge at a reduced rate. Some laptops will throttle their performance to reduce power consumption when using an underpowered charger, allowing the battery to charge slowly even while the laptop is in use.

Anyways, I guess I'll have to answer my own question. Testing the HP ZBook Power G11 (with the NVIDIA RTX 3000) showed that

- 45W via TB4 does NOT charge when on

- 60W via HP charger port does NOT charge when on

- 150W via charger port does charge when on

- 280W via TB4 + HP charger port does charge when on

- 100W via TB4 does charge when on (with similar estimate in Win11 than the 280W). I tested this with both a Dell and a HP charger.

The last one is what I wanted to know.