5090 Series GPU Installation - Power Safety and Guidance

The all new ZOTAC GAMING GeForce RTX™ 5090 series are here! With the great performance that comes with the cutting-edge NVIDIA Blackwell architecture, comes a sizable power requirement. Some users may have questions regarding powering the 5090 series graphics cards, and the steps in this article may help address those questions.

1. Get a PSU with the Right Wattage

The RTX 5090 requires a minimum power recommendation of 1000W, so make sure your system is equipped with a PSU of the right Wattage or above. We don't recommend powering your card with anything less.

The 5090 series graphics card can draw up to 600W alone under load, and that’s before considering the power draw from other components in the system. The more headroom you have with the power supply, the better, as it won’t be running near or at its maximum capacity consistently, and that allows for the absorption of power spikes, and your system would be more reliable in the long run.

As a rule of thumb, we recommend that the total load of your computer to be around 75% of the PSU’s rated power output, for an optimal PSU load balance.

2. Read the Power Supply User Manual

The power supply has many power connectors to support a variety of PC components. For example, most PSUs include a 24-pin cable to power the motherboard, a 4/8-pin cable to power the CPU, and additional cables to power 12V components and PCIe powered components such as a graphics cards, but the actual variety and number of cables may vary with each PSU.

PSUs come in either non-modular, semi-modular, or fully modular designs. For semi and fully modular designs, you will want to make sure that the correct cables are connected into the correct power sockets on the PSU. They should be labeled on the PSU unit itself, but check the user manual’s port overview/layout to be sure.

Fig. 1 PSU-Side Power Sockets

Different power supplies come with different port/cable configurations. For example, they can have different numbers of PCIe power ports and cables; some may even have a PCIe cable that connects to a single port on a PSU but splits into two plugs.

Fig. 2 PSU Splitter Cable

Newer PSU models can have a cable sometimes referred to as PCIe Gen 5, 12VHPWR, or 12V-2x6, in which a single power cable can support up to 600W for newer, high power devices such as the 5090.  

Due to the variety of combinations and configurations for each PSU model, we strongly recommend consulting the user manual that comes with your PSU before installing your GPU, or reach out to the PSU brand for additional support.

3. Use the correct power cable

1. Bundled Power Adapter

Every RTX 5090 series graphics card include a 4x-8-pin-to-16-pin adapter cable. Remember to use only the one bundled with the graphics card, which has been rated and tested to work safely with the 5090.

Fig. 3 4x-8-pin-to-16-pin adapter cable

More importantly, each 8-pin adapter should be connected to a single PCIe power source. Earlier we mentioned that some PSUs “may have a PCIe cable that connects to a single port on a PSU but splits into two plugs.” Even though the PCIe power connectors may split into more than one output, it is not advisable to use both when installing a Graphics Card.

The bottom line is: Do not use both heads of the split sides at the same time. When connecting PCIe cables to the 4x-8-pin-to-16-pin adapter cable, each side should only be connected to one socket. So, there should be 4 PCIe power cables connected to PSU, each connected to one 8-pin connector to power the GPU.  Zip tie/Velcro tie it down to keep things tidy and organized.

Fig. 4 Do this!

Fig. 5 DO NOT DO THIS!

2. PCIe Gen 5 cable

If your PSU supports a PCIe Gen 5 cable, make sure it’s rated to support up to 600W. This would be the ideal solution since it makes for a cleaner and easier install since less cables are needed, but only newer PSU models are ATX 3.0 or ATX 3.1 PCIe Gen 5 ready. If you’re unsure of the cable rating, check the PSU user manual or contact the manufacturer before installing the GPU.

Additional recommendations

Good System Airflow

A higher power draw, means more heat to be exhausted. Good airflow circulation is critical to a healthy system environment, since it will allow quicker exhaust of heat and constant intake of fresh air for optimal cooling. For the 5090, we recommend at least installing 3 120mm or larger case fans for good air circulation to cool the card, but if you can add more fans to the case, you should do so after considering its impact on the overall airflow inside the case.

Routine maintenance is also important. Depending on your case configuration, dust can build up quickly and constrict/degrade airflow intake and exhaust. Inspect, clean and clear dust build-up on fans and dust filters (if your case comes with them) on a routine basis, but how often you should clean them can vary greatly as it depends entirely on where the PC is placed, the environment, and even geo-location.

GPU Support

The long length, weightier cards, and bulkier size of the 5090 series graphics card can introduce possible sagging when installed in PC systems. It may appear right away or slowly over time. All 3 fan ZOTAC 50 series graphics card come bundled with a GPU Support Stand so be sure to use it and be sure to avoid contact with any moving parts such as the GPU fan or Case fans.