Table of Contents
Ubuntu - GPU - GPU Power Cable Guide
Many GPUs are power-hungry and have different power connectors.
- These power connectors are usually: 6-pin, 6+2-pin, 8-pin, and 12-pin.
Recommendation
Always use two separate cables whenever possible!!!
- A splitter cable can still be used, but only make use of one of the ends into each connector of the GPU.
ALERT: Do NOT use splitter cables to power graphic cards.
- See alert below.
- Always use two separate cables whenever possible!!!.
- A splitter cable can still be used, but only make use of one of the ends into each connector of the GPU.
GPU Power Cable Guide — Total Power Provided
| PCIe x16 Slot | 6-pin Connector | 8-pin Connector | 12-pin Connector | Total Power |
|---|---|---|---|---|
| 75W | — | — | — | 75W |
| 75W | 75W | — | — | 150W |
| 75W | 2 x 75W | — | — | 225W |
| 75W | — | 150W | — | 225W |
| 75W | 75W | 150W | — | 300W |
| 75W | — | 2 x 150W | — | 375W |
| 75W | — | 3 x 150W | — | 525W |
| 75W | — | — | 600W | 675W |
| 75W | — | — | 2 x 600W | 1275W |
Motherboard Power (PCIe x16 Slot)
The motherboard provides up to 75W of power to the GPU through the PCI Express x16 slot.
Most graphic cards require more power than that, usually provided through Power Connector Cables.
6-Pin Power Connector
A 6-pin power connector provides an additional 75W of power.
NOTE: This results in a total of 150W, when combined with the 75W of power from the motherboard.
- For most entry-level and mid-range graphics cards, this amount will suffice.
Multiple 6-pin Connectors
Some graphics cards have multiple 6-pin connectors.
Each 6-pin connector will provide 75W of power, so two separate 6-pin connectors will collectively provide 75W+75W = 150W.
NOTE: This results in a total of 225W, when combined with the 75W of power from the motherboard.
ALERT: Do NOT use splitter cables to power graphic cards.
- See alert below.
- Always use two separate cables whenever possible!!!.
- A splitter cable can still be used, but only make use of one of the ends into each connector of the GPU.
6-Pin & 8-Pin Power Connectors
Some mid-range graphic cards have both a 6-pin power connector and an 8-pin power connector.
Collectively this will provide 75W+150W = 225W of power.
NOTE: This results in a total of 300W, when combined with the 75W of power from the motherboard.
6+2-pin or 8-pin Power Connectors
A 6+2-pin connector is, for all intents and purposes, an 8-pin one.
- It is just divided into two parts, which could allow it to be used as a 6-pin power cable if need be.
These connectors provide 150W of power.
NOTE: This results in a total of 225W, when combined with the 75W of power from the motherboard.
Multiple 6+2-pin and 8-pin Power Connectors
Some graphics cards have multiple 8-pin connectors.
- Sometime double or even triple 8-pin set-ups.
A double 8-pin connector will provide 150W+150W = 300W.
A triple 8-pin connector will provide 150W+150W+150W = 450W.
NOTE: When combined with the 75W of power from the motherboard, these will result in:
- For a double connection, 375W of power.
- For a triple connection, 525W of power.
ALERT: Do NOT use splitter cables to power graphic cards.
Even though an 8-pin connector can supposedly handle 150W of power, it may not deliver that to the GPU.
- It all depends on the overall quality of the power supply in question and the cable being used.
- The 150W is from the ATX spec for PSUs; which is followed by virtually all consumer desktop hardware; but not all!
A single PCIe 8-pin cable and connectors maximum current rating is 12.5A, which is 150W (+12V x 12.5A); Watts = Volts x Amps.
- If the wires get too much power, they can melt; or worse, catch fire.
- The actual power a cable will and can carry depends on quite a bit more.
- This is why it is usually a bad idea to use splitter cables to power graphic cards.
- If you have a 400W graphics card, and you are powering it with a splitter; you are sending a whopping 27 Amps down a single set of wires.
- That is just asking for trouble as you are leaning very heavily on the quality of your PSU.
- Always use separate cables whenever possible!!!
- A splitter cable can still be used, but only make use of one of the ends into each connector of the GPU.
12-pin Power Connector
NVIDIA introduced the usage of a 12-pin Power Connector on newer RTX 3000 series GPUs.
These cables provide a whopping 600W of power.
NOTE: This results in a total of 675W, when combined with the 75W of power from the motherboard.
- The width of the 12-pin connector is the same as a standard 8-pin connector because the pins themselves are a fair bit smaller than usual.