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- Re: Compatibility between HP Z840 with 1125W power supply an...

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06-02-2025 09:56 AM
Good morning, I would like to know if I can install the GIGABYTE GeForce RTX 5070 Ti GPU in the HP Z840 workstation with a 1125W power supply, which only has three 6-pin connectors, while the GPU requires a 16-pin connector.
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06-02-2025 11:40 AM - edited 06-02-2025 11:42 AM
the quick answer is yes, however i strongly recommend using the HP 6 to 8 pin adapter as 3rd party 6to8 adapters can vary wildly in quality and those substandard ones using thinner coper wires and cheaper Molex connectors can be a fire hazzard
you will need 2 of these HP 6 to 8 adapters then use the nvidia 8 to high power adapters the first link is the workstation variant, the sec link is the consumer variant since your card is only 300 watt the cheaper consumer variant will work fine in your case
https://www.amazon.com/HP-Power-Supply-Adapter-N1G35AA/dp/B011Z74OGW
https://www.ebay.com/itm/144253153953
the z840 power supply is a "multirail' type supply where each power section is a separate unit with a specific wattage limit rather than the more common nowadays single rail supply where the total wattage is available on each power connector
note The Nvidia GeForce RTX 5070 Ti typically draws about 300 watts
06-02-2025 11:40 AM - edited 06-02-2025 11:42 AM
the quick answer is yes, however i strongly recommend using the HP 6 to 8 pin adapter as 3rd party 6to8 adapters can vary wildly in quality and those substandard ones using thinner coper wires and cheaper Molex connectors can be a fire hazzard
you will need 2 of these HP 6 to 8 adapters then use the nvidia 8 to high power adapters the first link is the workstation variant, the sec link is the consumer variant since your card is only 300 watt the cheaper consumer variant will work fine in your case
https://www.amazon.com/HP-Power-Supply-Adapter-N1G35AA/dp/B011Z74OGW
https://www.ebay.com/itm/144253153953
the z840 power supply is a "multirail' type supply where each power section is a separate unit with a specific wattage limit rather than the more common nowadays single rail supply where the total wattage is available on each power connector
note The Nvidia GeForce RTX 5070 Ti typically draws about 300 watts
06-06-2025 12:50 AM
Thank you so much for your reply.
As for power, the unit includes a 12 pin to 3x 8 pin power cable that is rated for the 300W power draw of the card. I was wondering if I need to connect just two cables with 6 to 8 pin adapters or all three?
06-06-2025 05:11 PM - edited 06-06-2025 05:12 PM
the NVidia high power adapter only comes in one model and is used for all cards using this connector style regardless of the cards wattage your cards draw is approx. 300 watts 75 watts comes via the pci-e slot the remainder 225 watts comes via the high power connector that means each of the 6 pin to 8 pin HP gpu connectors is supplying approx. 112 watts
so no in your case the 3rd connector is not used
and before i forget the HP 11250 watt supply has 3 GPU connectors, HOWEVER..... two of them are on the same cable!!
make sure the adapters are NOT connected to a cable with the two you need to split the load across the cable with only one GPU and connect the other adapter to the cable with the two gpu connectors
06-07-2025 09:29 AM
Thank you for your reply. The three cables are labeled G1, G2, and G3. How can I figure out which two cables are paired together? If I understood correctly, I should connect the GPU to the single cable and to one of the two split cables?
06-07-2025 09:00 PM - edited 06-07-2025 09:19 PM
again make sure the two 6 to 8 adapters are NOT connected to just the single GPU male power supplies gpu cable by using two 6 to 8 pin gpu connectors
you need to connect one 6 to 8 adapter to the HP power supplies gpu cable with the single male 6 pin connector, then connect the other 6 to 8 pin adapter to the power supplies GPU cable so two male 6 pin GPU power connectors are used
some people have used 6 pin to dual 8 pin adapters which is not recommended