Last updated: October 12, 2026 · ToneCooling Engineering Team
The ToneCooling GB300 liquid cold plate kit (part no. TC-BZP-GB300-01A) is a 4 GPU + 2 CPU (4G+2C) direct-to-chip copper cold plate set for GB300 NVL72-class compute trays. In our steady-state test, each GPU cold plate removed 1,066.94 W at 1.7 L/min with 12.06 kPa pressure drop and 0.0130–0.0133 °C/W thermal resistance. The kit is a standard product supplied to a published datasheet; samples are typically available in 4–6 weeks, and production lead time is normally 6–8 weeks, confirmed at quotation.
Request RFQDownload GB300 Datasheet (PDF)
What Is a GB300 NVL72 Liquid Cold Plate?
A GB300 NVL72 liquid cold plate is a copper plate with internal coolant channels that mounts directly on the GPU or CPU in a GB300-class compute tray. Heat passes through the thermal interface material into the plate and is carried away by the coolant to the rack manifold and CDU. GB300 NVL72 systems are designed for liquid cooling, so the cold plates are a core part of the server’s thermal path.
ToneCooling supplies these plates as a complete 4G+2C kit, so the GPU plates, CPU plates and loop hardware arrive as one validated set rather than separate parts.
GB300 Cold Plate Specifications (Measured)
All values below are from ToneCooling steady-state tests with pure water (test date 2026-03-20), as published in the GB300 datasheet (PDF, Rev B, no form required).
| Parameter | GPU cold plate | CPU cold plate |
|---|---|---|
| Flow rate | 1.7 L/min | 0.7 L/min |
| Heat load | 1,066.94 W | 485.46 W |
| Inlet / outlet temperature | 19.9 °C / 27.3 °C | 23.6 °C / 31.5 °C |
| Measured temperature | T1 34.1 °C / T2 33.8 °C | T1 34.3 °C |
| Temperature rise vs inlet | 14.2 °C / 13.9 °C | 10.7 °C |
| Pressure drop | 12.06 kPa | 10.39 kPa |
| Thermal resistance | 0.0133 / 0.0130 °C/W (T1 / T2) | 0.0220 °C/W |
| Thermal interface material | TC-5888 thermal paste | TC-5888 thermal paste |
What Is in the GB300 4G+2C Kit?
| Component | Qty | Description |
|---|---|---|
| GPU cold plate | 4 | Copper micro-channel cold plate |
| CPU cold plate | 2 | Direct-to-chip CPU cold plate |
| Manifold | 1 | Coolant supply / return distribution |
| Quick disconnect | 2 | Loop connection, color-coded |
| Hoses / tubes | 10 | Flexible coolant connections |
Surface finish is black textured baking paint. Pressure-drop data, leak test records and the STEP model are available on request.
Design Operating Envelope
The kit is designed for the following range. Final performance depends on system integration, so we recommend pressure-drop and thermal verification under your own conditions.
| Coolant | Pure water / PG25 |
| Flow per cold plate | 2–4 L/min |
| Pressure-drop design target | < 40 kPa @ 3 L/min |
| GPU heat load | 800–1,200 W per GPU |
| CPU heat load | 350–600 W |
| Inlet temperature | 20–30 °C |
| Working pressure | ≤ 3 bar |
How to Choose a GB300 Cold Plate
- Match the configuration: the TC-BZP-GB300-01A kit is a 4G+2C set; confirm your tray uses four GPUs and two CPUs.
- Check your loop budget: compare available flow and pressure drop at the rack manifold with the measured values above.
- Confirm coolant and inlet temperature: the kit is designed for pure water or PG25 at 20–30 °C inlet.
- Check connectors and routing: confirm quick-disconnect positions and hose routing against your tray and manifold.
- Need something different? Other layouts, connectors or heat loads are handled as custom designs — see our liquid cold plates overview.
GB300 vs. GB200 Cold Plates
GB300 and GB200 trays use different cold plate kits, so an existing GB200 set should not be assumed to fit or perform on GB300. Compare the published datasheets: the GB300 kit above, and our GB200 cold plate kit. All four standard AI server kits are listed in the datasheet center.
Why ToneCooling for GB300 Cold Plates
- Standard 4G+2C kit supplied to a published datasheet with measured values
- Our own manufacturing facility in Huizhou, China
- 100% helium leak testing on every kit (acceptance criteria per project); pressure and pressure-holding tests during production
- Thermal resistance, leak and flatness test reports available on request
- Samples typically 4–6 weeks; production normally 6–8 weeks, confirmed at quotation
- STEP model and test records available for engineering evaluation
For a quotation on a specific quantity, see the GB300 4G+2C quotation page or send an RFQ.
Need a GB300 Cold Plate Quote?
Send the platform (GB300 4G+2C), quantity, coolant, inlet temperature, flow per tray, allowed pressure drop and connector type. An engineer reviews every RFQ and replies by email with next steps. For a full input checklist, see the GB300 cold plate quotation guide.
Request the GB300 STEP Model or Test Report
Evaluating the kit? Ask for the STEP model, test report, or both.
GB300 Liquid Cold Plate FAQ
What is the part number of the ToneCooling GB300 cold plate kit?
The part number is TC-BZP-GB300-01A. It is a 4G+2C kit: four GPU cold plates, two CPU cold plates, a manifold, hoses and quick disconnects. A GB300 NVL72 rack has 72 GPUs and 36 Grace CPUs, so its GPU and CPU positions correspond to 18 kits (calculated: 72 ÷ 4).
What thermal resistance does the GB300 GPU cold plate achieve?
In our steady-state test with pure water, the GPU cold plate measured 0.0130–0.0133 °C/W at 1.7 L/min with a 1,066.94 W heat load. The CPU cold plate measured 0.0220 °C/W at 0.7 L/min and 485.46 W.
What is the difference between GB200 and GB300 cold plates?
They are different kits and are not interchangeable by default. The ToneCooling GB200 kit (TC-BZP-GB200-01A) is rated 1,200 W + 1,200 W + 300 W for two GPUs and one Grace CPU, while the GB300 4G+2C kit (TC-BZP-GB300-01A) uses separate cold plates for four GPUs and two CPUs per tray. Compare the GB200 cold plate kit datasheet with the GB300 table above before reusing any hardware.
How much does a GB300 cold plate kit cost?
It is quoted per project, because quantity, coolant, connectors and validation scope change the cost. Send an RFQ with your GB300 4G+2C requirements and an engineer replies by email with a quotation. The kit is designed for pure water or PG25 at a 20–30 °C inlet and up to 3 bar working pressure.
How long do GB300 cold plate samples take?
Samples are typically available in 4–6 weeks, including design review, and custom samples are available from a single piece. Production lead time is normally 6–8 weeks and is confirmed in the quotation.
Is every GB300 cold plate kit leak tested, and can I get the test data?
Yes. Every kit goes through 100% helium leak testing, with acceptance criteria set per project. Thermal resistance, leak and flatness test reports and the STEP model are available on request through the form above, and the GB300 datasheet downloads without a form.
Measured values are from ToneCooling steady-state tests with pure water (2026-03-20). Final thermal and hydraulic performance depends on system integration, flow distribution, coolant, clamping force, TIM and rack cooling architecture. GB300 platform-compatible; NVIDIA and GB300 are trademarks of NVIDIA Corporation and no affiliation or endorsement is implied. Further reading: NVIDIA GB300 NVL72 platform, what is a cold plate, coolant distribution units.
Related guides
- GB300 liquid cooling requirements — heat load, flow and CDU sizing
- Request a GB300 cold plate quote — 4 GPU + 2 CPU system
- GPU cold plates — GB300, GB200, H200 and H100
- GB200 cold plate kit — datasheet values
- H200 liquid cooling plate — HGX H200 kit
- H100 cooling plate — HGX H100 kit
