Ubuntu - GPU - Troubleshooting - System crashes when running a GPU intensive process

Check the cables between the PSU and the GPU.

Many recent GPUs require multiple power cables to be plugged in.
Ensure that if a splitter cable is used, that only one of the cables of this splitter is plugged into the GPU.

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 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.

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