Liquid takes more heat off each chip.液体从每颗芯片带走更多热量。

1. Coolant channels.冷却液通道。
2. Cold plate (metal).冷板（金属）。
3. Thermal interface material, above and below the lid.导热界面材料，封盖上下各一层。
4. Lid (heat spreader) over the die.封盖（均热盖），罩在芯片上。
5. Die (silicon). Heat starts at hot spots on its circuit side, here at the bottom.芯片裸片（硅）。热量产生于电路面上的热点，图中在底部。
6. Sealed cover over the etched channels (not published; drawn generic).覆盖刻蚀通道的密封盖（结构未公开，示意画法）。

Cold-plate heat crosses the interface layers and the lid; etched channels bring the coolant to the silicon. Drawn after Microsoft (2025) and Purdue (2023).冷板方案的热量要穿过界面材料和封盖；刻蚀通道让冷却液直接到达硅片。绘制依据：Microsoft（2025）、Purdue（2023）。

1. Coolant channels: in a long channel the coolant warms along the way, and friction grows with length.冷却液通道：在长通道里，冷却液沿途升温，摩擦阻力随长度增加。
2. Cold-plate base (metal).冷板底座（金属）。
3. Thermal interface material between the plate and the die.冷板与芯片之间的导热界面材料。
4. Die (silicon): the heat source.芯片裸片（硅）：热源。
5. Printed manifold: feeds coolant down and takes it back up at many points, so each path is short.3D 打印歧管：在许多位置向下供液、向上回液，每条流程都很短。
6. Nozzle plate: jets strike the die itself, with no interface layer (drawn single-phase; the Purdue project boils the coolant).喷嘴板：射流直接冲击芯片本身，中间没有界面材料（图示为单相；普渡项目让冷却液沸腾）。

Short paths and jets thin the warm layer at the wall, so heat leaves faster; the cost is pumping power. Drawn after HRL (2026) and Purdue (2023).短流程和射流能减薄壁面处的热边界层，热量散得更快；代价是泵功。绘制依据：HRL（2026）、Purdue（2023）。

1. Pump: drives liquid refrigerant out to the racks.泵：把液态制冷剂送往机柜。
2. Cold plate: the refrigerant boils on the chip and leaves as liquid plus vapour; orange marks the heat the vapour carries, its temperature barely rises.冷板：制冷剂在芯片上沸腾，以气液混合物流出；橙色表示蒸汽带走的热量，其温度几乎不升高。
3. Condenser: the vapour condenses and gives its heat to facility water (a brazed plate exchanger); air-cooled units use a coil and fans instead.冷凝器：蒸汽冷凝，把热量交给设施水（钎焊板式换热器）；风冷型改用盘管和风机。
4. Control valve on the facility water.设施水调节阀。
5. CDU: pump and condenser in one unit; the condensed liquid returns to the pump.CDU：泵和冷凝器在同一台设备内；冷凝后的液体回到泵。

Boiling takes up heat as latent heat, so each litre of flow carries more heat at a nearly steady temperature. Drawn after Vertiv (2025).沸腾以潜热吸热，所以每升流量能带走更多热量，温度几乎不变。绘制依据：Vertiv（2025）。

1. Plug: the half with the outer mating shape; its end connects to a port.插头：外侧配合的一半，尾端接设备接口。
2. Socket: the half with the inner mating shape; its end takes a hose.插座：内侧配合的一半，尾端接软管。
3. Plug valve: a spring poppet that closes the nose when apart (internals are the maker's choice; drawn generic).插头阀：弹簧阀芯，断开时封住端口（内部结构由厂家自定，此为示意）。
4. Socket valve: a fixed stem and a spring sleeve that closes around it when apart.插座阀：固定阀杆，断开时由弹簧套筒围住它封闭。
5. Seal on the sealing surface that the specification fixes, so any maker's plug fits.密封圈，位于规范规定的密封面上，任何厂家的插头都能配合。
6. Latch on a hand-mate socket; blind-mate halves are aligned and held by the rack instead.手插型插座上的锁扣；盲插型则由机柜负责对准和固定。

Each half closes itself as they part, so little coolant spills; the spec fixes the mating shapes, not the valves. Drawn after OCP UQD/UQDB v2.0.0.两半分开时各自关闭，只漏出极少冷却液；规范规定配合形状，不规定阀门结构。绘制依据：OCP UQD/UQDB v2.0.0。

1. Plate heat exchangers: the specification uses three dual-pass units in parallel.板式换热器：规范采用三台双流程换热器并联。
2. Control valve on the facility water; by default it holds the approach constant.设施水调节阀：默认调节开度，使接近温差保持恒定。
3. Pumps (N+1, one drawn); by default they hold a fixed pressure difference.水泵（N+1 冗余，图中画一台）：默认维持恒定压差。
4. Approach: IT-loop supply leaving minus facility water entering (the Deschutes definition); 3 °C at 2,000 kW is the specification's target.接近温差：离开的 IT 回路供液温度减去进入的设施水温度（Deschutes 规范的定义）；2,000 kW 时 3 °C 是规范的目标值。
5. Temperature sensors on all four connections.四个接口上都有温度传感器。
6. Racks: cold plates on the chips warm the IT loop.机柜：芯片上的冷板使 IT 回路升温。

A smaller approach lets the facility water run warmer for the same IT supply temperature. Drawn after OCP Project Deschutes v1.0.0.接近温差越小，在 IT 供液温度不变时，设施水就可以越暖。绘制依据：OCP Project Deschutes v1.0.0。

1. Drive (variable frequency): sets the speed; its losses leave as heat (orange arrows).变频器：调节转速；其损耗以热的形式散出（橙色箭头）。
2. Motor: IE5 efficiency class on some data-centre products (vendor claim).电机：部分数据中心产品为 IE5 能效等级（厂商说法）。
3. Pump: its hydraulic losses end up as heat in the water.水泵：水力损失最终变成水中的热量。
4. EU: MEI rates the pump alone, shaft to water; at least 0.4 since 2015.欧盟：MEI 只考核水泵本体（从泵轴到水）；2015 年起不低于 0.4。
5. US: PEI rates pump and motor, plus the speed control for the variable-load rating; at most 1.00.美国：PEI 考核水泵加电机，变负荷评级还包括调速控制；不高于 1.00。

Losses arise in the drive, the motor and the pump; each rule sets a floor for part of that chain. Drawn after 10 CFR 431 and EU 547/2012.损耗分别出在变频器、电机和水泵；各项法规只为其中一段设下限。绘制依据：10 CFR 431、欧盟 547/2012。

1. Throttled at full speed: a valve burns the extra head, so power falls only a little.全速节流：阀门消耗多余扬程，功率只略有下降。
2. Speed control holding a fixed pressure (or against static head): power falls more slowly.调速但保持固定压差（或存在静扬程）：功率下降较慢。
3. Speed control with no pressure floor: power falls roughly with the cube of flow (affinity laws).调速且无压差下限：功率约按流量的三次方下降（相似定律）。

Slowing a pump cuts power far more than throttling it; the cube law is the best case. Drawn after DOE pump and fan sourcebooks.降速比节流省电多得多；三次方关系是最理想的情况。绘制依据：DOE 水泵指南、DOE 风机指南。

1. Impeller, fixed to the rotor: the motor sits inside its hub.叶轮，固定在转子上：电机位于其轮毂内。
2. Rotor with permanent magnets, turning outside the stator (external rotor).带永磁体的转子，在定子外侧旋转（外转子）。
3. Stator coils, fixed to the flange.定子线圈，固定在法兰上。
4. Electronics: switch the coil currents (electronic commutation) and set the speed from the signal.电子模块：切换线圈电流（电子换向），并按信号调节转速。

Built-in electronics commutate the motor and set its speed, so no separate drive is needed. Drawn after REF Industry (2026) and Wikipedia (EC motor).内置电子模块完成电机换向并调节转速，无需外置变频器。绘制依据：REF Industry（2026）、Wikipedia（EC 电机）。

1. Airflow rises in step with speed.风量与转速成正比。
2. Pressure rises with the square of speed.压力与转速的平方成正比。
3. Power rises with the cube of speed, so a fan at part speed needs far less power.功率与转速的三次方成正比，所以风机降速运行时功耗大幅减少。

For one fan in a fixed system, power follows the cube of speed, so slowing down at part load saves most. Drawn after DOE fan sourcebook (2003).固定系统中的单台风机，功率随转速的三次方变化，所以部分负荷时降速最省电。绘制依据：DOE 风机指南（2003）。

1. Cycle for cold leaving water: low evaporating pressure, large lift.低温出水的循环：蒸发压力低，提升大。
2. Cycle for warm leaving water: the evaporator runs warmer, so the lift is small.高温出水的循环：蒸发温度更高，提升小。
3. Suction limit of a conventional compressor; warm water needs a raised limit (vendors state maximum leaving water of 28–45 °C).常规压缩机的吸气温度上限；高温出水需要更高的上限（厂商标称最高出水温度 28–45 °C）。
4. Compression: its width is the work per kilogram, much shorter for warm water.压缩过程：横向宽度即每千克制冷剂的功，高温出水时短得多。
5. Saturation dome: inside it the refrigerant is part liquid, part vapour. Thin line: one constant temperature.饱和线：线内制冷剂为气液混合。细线：一条等温线。

Warmer leaving water raises the evaporating pressure, so the compressor lifts less but must accept a warmer suction. Drawn after Danfoss (2021).出水温度升高使蒸发压力升高，压缩机提升变小，但必须能接受更高的吸气温度。绘制依据：Danfoss（2021）。

1. Server sleds: water boils in a heat sink on each chip, below atmospheric pressure; orange marks the heat the vapour carries; its temperature barely rises.服务器托架：水在每颗芯片的散热器中于负压下沸腾；橙色表示蒸汽带走的热量，其温度几乎不升高。
2. Condenser sled in the rack: the vapour condenses and gives its heat to the water that runs to the dry cooler.机柜内的冷凝器托架：蒸汽冷凝，把热量交给流向干冷器的水。
3. Pump sled (the slides do not show its piping; drawn on the liquid line).泵托架（报告未给出其管路，图中画在液体管路上）。
4. Dry cooler: outdoor air cools the water through a finned coil; no water is sprayed or evaporated.干冷器：室外空气经翅片盘管冷却水，不喷水，也不蒸发水。
5. Fans draw the outdoor air through the coil.风机抽吸室外空气流过盘管。
6. Temperature ladder, not to scale: 40 °C air is the team's design target; 50–55 °C is the dry-cooler water in its completed rack test.温度阶梯（未按比例）：40 °C 空气是团队的设计目标；50–55 °C 是其已完成机柜测试中干冷器供水的温度。

Warm coolant lets a dry cooler reject chip heat to hot outdoor air without evaporating water. Drawn after University of Florida (2025).冷却液温度够高，干冷器就能把芯片热量排到炎热的室外空气中，而不必蒸发水。绘制依据：佛罗里达大学（2025）。

1. Every class starts at 2 °C; the number in its name is the upper limit of the facility water.所有等级下限均为 2 °C；名称中的数字是设施水温度上限。
2. W+ (was W5): its name sets no upper limit.W+（原 W5）：名称不设上限。
3. TC 9.9 expected that direct liquid-cooled products able to use W45 today may give way to higher-power ones that need W32, and facility water may in time drop to W27.TC 9.9 预计，如今能用 W45 的直接液冷产品可能被只能用 W32 的更高功率产品取代，设施水温最终可能降到 W27 范围。

Each class is named by its upper limit; equipment rated for a class must run at full performance across its range. Drawn after ASHRAE TC 9.9 (2021).每个等级以温度上限命名；标定某等级的设备须在整个范围内保持全性能运行。绘制依据：ASHRAE TC 9.9（2021）。

1. PLC: reads the sensors, drives the pump and the valve, and lets CDUs run in parallel.PLC：读取传感器、控制水泵和阀门，并支持多台 CDU 并联运行。
2. Pressure difference between IT supply and return: by default the pump speed holds it fixed.IT 供液与回液之间的压差：默认通过调节水泵转速使其恒定。
3. Pump (N+1, one drawn).水泵（N+1 冗余，图中画一台）。
4. Temperatures of the IT supply and the facility supply: by default the valve holds their difference, the approach, fixed.IT 供液温度和设施水供水温度：默认通过阀门使两者之差（接近温差）恒定。
5. Control valve on the facility water.设施水调节阀。
6. Leak-detection rope in three zones (where they run is not specified).漏液检测绳，分三个区（敷设位置规范未写明）。

Both default loops hold a set point; the specification leaves response to load steps for later versions. Drawn after OCP Project Deschutes v1.0.0.两个默认回路都只维持设定值；对负荷阶跃的响应，规范留待后续版本补充。绘制依据：OCP Project Deschutes v1.0.0。

1. Power cap: the GPUs' power limit is raised step by step at the start of a run.功率上限：训练开始时逐步提高 GPU 的功率上限。
2. Energy storage: capacitors in the power shelves charge when GPU power is low and discharge when it is high.储能：电源架中的电容在 GPU 功率低时充电、高时放电。
3. Power burner: when the work stops, the GPUs keep drawing power for a while, then taper off.功率燃烧器：任务停止后，GPU 继续耗电一段时间，再逐渐降低。

Smoothing evens out what the grid sees; inside the rack the GPU load, and its heat, still swings. Drawn after NVIDIA (2025).平滑的是电网看到的负荷；机柜内 GPU 的负荷及其发热仍在波动。绘制依据：NVIDIA（2025）。

1. Typical excess heat: generally 25–40 °C.一般余热：通常 25–40 °C。
2. High-temperature liquid cooling: return above 40 °C, in some cases 65 °C; the newest hardware often does not accept it.高温液冷：回水高于 40 °C，个别可达 65 °C；最新硬件往往不接受这么高的水温。
3. District-heating return: OCP lists it among uses that take heat above 45 °C.区域供热回水：OCP 将其列为接收 45 °C 以上热量的用途之一。
4. Heat pump: lifts the heat to the temperature the user needs, using electricity; the smaller the lift, the less it uses.热泵：消耗电能，把热量提升到用户所需温度；提升越小，耗电越少。

Most data-centre heat is too cool for a heat network, so a heat pump lifts it; hot liquid cooling may need no lift. Drawn after OCP Heat Reuse (2025).多数数据中心余热温度不够热网使用，需要热泵提升；高温液冷可能无需提升。绘制依据：OCP 热回收（2025）。

1. Tank with a lid: the dielectric liquid stays liquid the whole way round.带盖浸没槽：介电液体全程保持液态。
2. Servers stand on end in the liquid, with no server fans; the liquid warms as it flows past them.服务器竖立在液体中，不用服务器风扇；液体流过时升温。
3. Pump: moves the liquid through the tank and the exchanger.泵：推动液体流经浸没槽和换热器。
4. Plate exchanger: gives the heat to facility water. One maker rates its tank with the liquid held at a 50–55 °C setpoint (vendor claim).板式换热器：把热量交给设施水。一家厂商的额定工况把液体保持在 50–55 °C 设定值（厂商说法）。

The liquid never boils: a pump moves it past the servers and through an exchanger to facility water. Drawn after ORNL (2025) and an OCP tank datasheet.液体始终不沸腾：泵推动它流过服务器，再经换热器把热量交给设施水。绘制依据：ORNL（2025）、OCP 浸没槽数据表。

1. Sealed lid: keeps the vapour in the tank.密封盖：把蒸汽留在槽内。
2. Servers in the liquid, which boils on their hot parts.浸在液体中的服务器，液体在发热部件上沸腾。
3. Vapour rises; orange marks the heat the vapour carries; its temperature barely rises.蒸汽上升；橙色表示蒸汽带走的热量，其温度几乎不升高。
4. Condenser coil under the lid: coolant inside turns the vapour back to liquid, which drips into the pool.盖下的冷凝盘管：管内冷却液把蒸汽冷凝成液体，滴回液池。
5. Pump and fan radiator carry the heat away (as in the tank that ORNL tested).泵和风冷散热器把热量带走（与 ORNL 测试的槽相同）。

The fluid boils on the chips and condenses on a coil under the lid, so no large pump moves it. Drawn after ORNL (2025).液体在芯片上沸腾、在盖下盘管上冷凝，所以不需要大功率泵来输送它。绘制依据：ORNL（2025）。

1. Servers: their fans push room air through and heat it.服务器：自带风扇把机房空气吸入并加热。
2. Door coil: rows of water tubes with fins; the air leaves at about room temperature, so the rack adds little heat to the room.后门盘管：多排带翅片的水管；空气离开时接近室温，机柜几乎不向机房散热。
3. Fans on an active door make up for the coil's air resistance.主动背板上的风扇，用来抵消盘管增加的风阻。
4. Water in (cold) and out (warm): conventional doors need cold water, class W17 or W27.进水（冷）与回水（温）：常规背板需要较冷的水，即 W17 或 W27 等级。
5. Hybrid option (dashed): cold plates send part of the heat to liquid; one consortium analysis assumes at least 50% (not a test).混合方案（虚线）：冷板把部分热量直接交给液体；一项联盟分析假设至少 50%（非测试）。

The coil takes the heat out of the server exhaust before it reaches the room, so the room sees almost none of it. Drawn after OCP door HX whitepaper.盘管在服务器排风进入机房之前就把热量带走，机房几乎感受不到这部分热量。绘制依据：OCP 背板换热器白皮书。

1. Rack: cold plates on the chips; the coolant warms as it passes them.机柜：芯片上装有冷板，冷却液流过时升温。
2. Liquid-to-air coil: the coolant gives its heat to room air. Vendors rate units at an approach (11 °C, 15 °C; vendor claims) without defining it.液-气盘管：冷却液把热量交给机房空气。厂商按接近温差标称额定值（11 °C、15 °C，厂商声明），但未说明其定义。
3. Fans blow room air through the coil and back into the hall.风机让机房空气流过盘管，再排回机房。
4. Pump: moves the coolant between rack and sidecar; no facility water is connected.泵：在机柜与侧柜之间输送冷却液；不接设施水。
5. Room air conditioning: it must remove all the rack's heat; in the 24 kW unit test, loads above its capacity raised the room temperature.机房空调：必须带走机柜的全部热量；在 24 kW 单元测试中，超过其冷量的负荷使房间温度上升。
6. Hot air that recirculates to the sidecar's intake lowers its performance.热风回流到侧柜进风口，会降低其性能。

A sidecar needs no facility water, but all the heat it rejects becomes load on the room's air cooling. Drawn after Heydari et al. (2023) and CoolIT AHx180.侧柜不需要设施水，但它排出的全部热量都成为机房空调的负荷。绘制依据：Heydari 等（2023）、CoolIT AHx180。

1. Maker's filter before the fluid is packed: 50 µm or finer, 25 µm or less preferred.生产商在包装前过滤：50 µm 或更细，优先 25 µm 及以下。
2. Fluid as supplied (specification limits): PG25 with 25–28 % propylene glycol by weight and chloride below 5 ppm; water-based coolant at pH 8.0–10.5.出厂液体（规范限值）：PG25 含 25–28%（质量）丙二醇，氯化物低于 5 ppm；水基冷却液 pH 8.0–10.5。
3. CDU inline filter on the full flow, often 25 or 50 µm; it protects the heat exchanger (facility water on its far side) and quick disconnects.CDU 全流量管路过滤器，常见 25 或 50 µm，保护换热器（另一侧为设施水）和快速接头。
4. Sidestream filter: a small part of the flow passes it continuously; strongly recommended above 250 gallons of fluid.旁滤器：一小部分流量持续流经；冷却液超过 250 加仑时强烈建议设置。
5. Cold-plate channels: the narrowest passages in the loop.冷板通道：回路中最窄的流道。

The narrowest cold-plate channel sets how fine the loop's filters must be. Drawn after OCP PG25 v1.0.0, OCP PG25 guidelines and OCP water coolant v1.3.冷板最窄的通道决定了回路过滤器要有多细。绘制依据：OCP PG25 v1.0.0、OCP PG25 指南、OCP 水基冷却液 v1.3。

1. Free-cooling coil on the air inlet side of the condenser coil: outdoor air pre-cools the return water.自然冷却盘管，装在冷凝盘管的进风侧：室外空气先给回水预冷。
2. Condenser coil: rejects the heat of the refrigerant circuit.冷凝盘管：排出制冷循环的热量。
3. Three-way valve: sends the return water through the free-cooling coil, or past it (dashed) when the outdoor air is too warm.三通阀：把回水送进自然冷却盘管；室外空气太热时让回水绕过盘管（虚线）。
4. Evaporator: cools the water the rest of the way to the set point.蒸发器：把水继续冷却到设定温度。
5. Compressor (refrigerant circuit simplified).压缩机（制冷回路已简化）。
6. Fans draw outdoor air through both coils.风机抽吸室外空气依次流过两组盘管。

Return water meets the outdoor air first; the compressors make up only what the air cannot. Drawn after Daikin Applied (2020) and Kaltra (2023).回水先由室外空气冷却，压缩机只补足空气做不到的部分。绘制依据：Daikin Applied（2020）、Kaltra（2023）。

1. Full free cooling: air well below the leaving water; compressors off. One vendor states 13 °C ambient (vendor claim).完全自然冷却：气温远低于出水温度，压缩机停机。有厂商称环境 13 °C 即可实现（厂商声明）。
2. Mixed: air below the return water; the coil pre-cools, the compressors finish.混合模式：气温低于回水温度；盘管预冷，压缩机补足。
3. Mechanical: air above the return water; the valve bypasses the coil.机械制冷：气温高于回水温度；三通阀让水绕过盘管。

Warmer water widens the free and mixed ranges. Card 8 shows the machine. Drawn after Daikin Applied (2020).水温越高，自然冷却和混合模式的范围越宽。卡片 8 展示了机组结构。绘制依据：Daikin Applied（2020）。

1. Outside air on a hot day, at its dry-bulb temperature.高温日的室外空气，处于干球温度。
2. Wetted pad (or mist): water evaporates and cools the air toward its wet-bulb temperature before the coil.湿帘（或喷雾）：水分蒸发，使空气在进入盘管前降温，趋近湿球温度。
3. Water to the pads, used only above a switch point; the water used counts in WUE, litres per kWh of IT energy.湿帘供水，只在超过切换温度时使用；用水计入 WUE，即每 kWh IT 能耗的升数。
4. Coil: fluid from the cooling loop gives its heat to the air and leaves colder.盘管：来自冷却回路的液体把热量交给空气，降温后流出。
5. Fans draw the air through and can slow down when the air is cooler.风机抽风穿过盘管；空气更凉时可以降速。

Evaporation cools the air toward its wet bulb, so the coil reaches a colder fluid on hot days but uses water. Drawn after engrXiv preprint (2026).蒸发让空气趋近湿球温度，盘管在高温日能把液体冷却得更低，但要耗水。绘制依据：engrXiv 预印本（2026）。

1. Corrugated plates: thin metal sheets; the ridges stir the flow and hold the plates apart.波纹板：薄金属板，波纹扰动流体并撑开板间距。
2. IT-loop channels: liquid back from the racks flows down and cools.IT 回路通道：从机柜回来的液体向下流动并降温。
3. Facility-water channels: water flows up, against the IT loop, and warms.设施水通道：设施水向上逆流并升温。
4. Approach: IT-loop supply leaving minus facility water entering (the Deschutes definition).接近温差：离开的 IT 回路供液温度减去进入的设施水温度（Deschutes 规范的定义）。

In counterflow across thin plates, the IT-loop supply leaves only a few degrees above the entering facility water. Drawn after OCP Project Deschutes v1.0.0.薄板两侧逆流换热，IT 回路供液出口温度只比进入的设施水高几度。绘制依据：OCP Project Deschutes v1.0.0。

1. Spec table: approach of the two-pass exchanger at equal flow on both sides (consortium specification).规范表格：两侧流量相同时双流程换热器的接近温差（联盟规范）。
2. Intermediate exchanger that keeps the dry-cooler glycol loop small: its approach was not found in a primary source.中间换热器，用来缩小干冷器乙二醇回路：其接近温差未在一手来源中找到。
3. CDU exchanger: specifications and vendors quote 2–5 °C at megawatt scale.CDU 换热器：规范和厂商在兆瓦级标称 2–5 °C。

Approach grows with load for a given exchanger, and each exchanger in series adds its own step. Drawn after OCP Project Deschutes v1.0.0 and Alfa Laval.同一台换热器的接近温差随负荷增大；串联的每台换热器都会再加一级温差。绘制依据：OCP Project Deschutes v1.0.0、Alfa Laval。

1. Power shelves turn AC into 54 V DC inside the rack; today's largest racks hold up to eight.电源架在机柜内把交流电变为 54 V 直流；目前最大的机柜最多装 8 个。
2. 54 V copper busbar to the trays; above about 200 kW per rack it hits space and copper limits (vendor claim).通往托盘的 54 V 铜母排；单柜超过约 200 kW 时会触及空间和用铜的极限（厂商声明）。
3. DC/DC converters in the rack take 800 V DC on two conductors (vendor plan from 2027).机柜内的 DC/DC 变换器接入两根导体的 800 V 直流（厂商计划，2027 年起）。
4. Separate power rack (sidecar) feeding ±400 V DC to the IT rack, which converts it down again (DC/DC) (draft specification 0.7.0).独立的电源柜（侧柜）向 IT 机柜输送 ±400 V 直流，IT 机柜内再经 DC/DC 变换（规范草案 0.7.0）。
5. Compute trays.计算托盘。

Higher voltage carries the same power with less current, so less copper and fewer shelves in the rack. Drawn after NVIDIA (2025) and OCP Diablo 400 v0.7.0.电压越高，输送同样功率所需电流越小，机柜内的铜材和电源架就越少。绘制依据：NVIDIA（2025）、OCP Diablo 400 v0.7.0。

1. Liquid: the manifold feeds cold plates on the chips in every tray.液冷：分水器为每个托盘中芯片上的冷板供液。
2. Air: a fan in each tray cools drives, risers and network cards.风冷：每个托盘内的风机冷却硬盘、转接板和网卡。
3. GB200 NVL72 rack in QCT's liquid-cooled rack system (vendor document): 115 kW by liquid and 17 kW by air.QCT 液冷机柜系统中的 GB200 NVL72 机柜（厂商资料）：液冷 115 kW，风冷 17 kW。
4. 1 MW rack, the target of both high-voltage routes; the figure is electrical power, and no source gives its liquid share.1 MW 机柜是两条高压路线的目标；该数字是电功率，没有来源给出其液冷占比。

Today liquid carries most of the rack's heat; a 1 MW rack is several times larger. Drawn after QCT (2025) and NVIDIA (2025).如今液体带走机柜的大部分热量；1 MW 机柜则是其数倍。绘制依据：QCT（2025）、NVIDIA（2025）。