Applies to: Two exact source/dock/host budget examples with separately powered monitors and explicitly assumed0W external bus-powered peripheral load. Arithmetic compares documented ceilings and declared operating targets; no actual draw or negotiation measured.
- video
- Host → DKT31 video output → independently powered U2720Q.
- data
- Host ↔ DKT31 ↔ peripheral; peripheral demand remains separately identified.
- power
- Exact USB-PD supply → DKT31 PD input; manufacturer reserves15W; remaining documented ceiling → host.
Worked documentary examples
A1289 C1 → DKT31 →14-inch2021 M1Pro,67W budget target
Documented outcome: Documented source/reserve/output arithmetic; hypothetical operating allocation
- Anker737 A1289 C1 alone offers20V5A. DKT31 input cap100W,15W manufacturer reserve, host cap85W. MacBookPro14-inch2021 M1Pro USB-C charging;67W budgeting target uses its base-model included-adapter rating, not a constant draw. U2720Q uses AC; no other external USB peripherals attached, assumed external bus load0W.
- Use a documented5A USB-C power cable from bank C1 to dock PDinput; attached dock host cable goes to the Mac.
- 100W input ceiling minus15W reserved gives85W host ceiling;67W declared host target leaves18W ceiling margin. Neither is a measured delivered value.
- The15W reserve remains assigned to dock/internal services; the0W external-peripheral assumption does not make the reserve available to the host. Connect the monitor by DP with independent AC power.
- A changed source allocation, cable or added peripheral requires a new budget. Confirm actual host charging status separately; no charging time is promised.
GW8L7 → DKT31 →14-inch2021 M1Pro,25W low-demand budget target
Documented outcome: Documented lower-input arithmetic with explicit operating assumption
- Google45W GW8L7 fixed20V2.25A option; DKT31 publishes15W reserve. MacBookPro14-inch2021 M1Pro charging over USB-C. Declared hypothetical host operating-plus-charge target25W; this is an assumption, not an OEM minimum or measurement. Independently powered U2720Q; no external bus-powered peripherals, assumed0W.
- Use exact documented source/cable/port roles; do not assume the dock still supplies85W on45W input.
- 45W minus15W leaves at most30W as the conditional host ceiling; compared with the declared25W target, arithmetic margin is5W.
- If the real host workload needs more than30W, sufficiency fails despite a working display. The15W dock reserve and0W external-peripheral assumption remain separate.
- Confirm actual negotiated input and observed battery behavior through normal manufacturer UI before relying on a workload. No physical negotiation or battery test was performed.
Your next useful observation
Record exact occupied source ports and host configuration, then replace declared load targets with applicable documented requirements or actual observations without claiming this site measured them.
Keep these limits
- 0W external peripheral draw and67W/25W host budgeting targets are explicit operating assumptions, not measurements. The67W reference is the base8-core M1Pro included-adapter rating, not every configuration's need.
- Actual negotiated contract, host workload, battery charge rate and margin remain untested; no fixed/PPS/EPR calculator change.
Source documents, revisions and inspection methods
Anker737 Power Bank PowerCore24K
Anker · A1289; live revision unavailable
Specifications: capacity; C1input; C1/C2output;140Wtotal
Inspected 2026-10-23 by public_page. Primary HTML page read directly in web reader; relevant body text and named table/section inspected. Not search-excerpt-only evidence. AI source review, no independent human review or hardware validation.
Exact bank outputs and capacity. No site charging test.
Read the original sourceSafety, Warranty & Regulatory Guide for Google 45W USB-C Charger
Google · ©2024; live revision unavailable
Regulatory Information Mexico → Modelo GW8L7; output profiles
Inspected 2026-10-23 by public_page. Primary HTML body / relevant table inspected; AI-assisted source reading, no independent human review or hardware validation.
GW8L7 exact regional model fixed/PPS outputs, not a phone-request trace.
Read the original sourceMacBook Pro 14-inch (2021) Technical Specifications
Apple · 2021 model; revision not stated
Display Support; Charging and Expansion
Inspected 2026-10-23 by public_page. Primary HTML relevant text/tables inspected; AI-assisted source reading, no independent human review or hardware validation.
M1 Pro versus M1 Max native capacity.
Read the original sourceDKT31CDHPD3 Quick-Start Guide
StarTech.com · Manual Revision 2022-12-02 1:28 PM
pp.1–2: port roles, power and display connection
Inspected 2026-10-23 by public_pdf_text. Primary PDF relevant text/tables inspected; AI-assisted source reading, no independent human review or hardware validation.
One display, DP Alt Mode, USB data and 100W/85W PD split.
Read the original sourceDKT31CDHPD3 Datasheet
StarTech.com · Revision not stated
Special Notes; Power; Maximum Laptop Charging; Displays Supported
Inspected 2026-10-23 by public_pdf_text. Primary PDF relevant text/tables inspected; AI-assisted source reading, no independent human review or hardware validation.
One-display dock, 15W reservation and85W host maximum.
Read the original sourceDell U2720Q/U2720QM User’s Guide
Dell · 2020-01 Rev. A00
USB-C Prioritization; Plug-and-Play; Preset Display Modes
Inspected 2026-10-23 by public_pdf_text. Primary PDF text and relevant table inspected; AI-assisted source reading, no independent human review or hardware validation.
Exact U2720Q modes and USB-C video/data priority; not U2723QE.
Read the original sourceSource-documented education. Hardware behavior and independent human review have not been performed for these examples.