Hi, I'm new to components and I see here that it's for PCIe 5, and it seems to me that only AMD has PCIe 5 for graphics cards.
Does this mean that it won't work with Nvidia 40 series or does it also support PCIe 4.0?
Short version: This power supply supports the 4000 series.
Long version: You may be confusing some things. As of now, there are no PCIe 5.0 graphics cards, even the 7900XTX is connected to the motherboard through PCIe 4.0. PCIe in this context is the interface between your graphics card and the rest of the system. This interface also supplies the graphics card with power, but unfortunately only up to 75 watts.
The cables between the power supply and the graphics card are similarly called PCIe connectors. The 6-pin offers 75 watts, the 6+2-pin offers 150 watts. My 7900XTX needs three 8-pins. If you are interested in the 4000 Nvidia series, you will use the 12 pin that Nvidia introduced with the 3000 series.
Should work without problems with Nvidia's 40 series, you also only need a single 600w cable and no adapter for the latest Nvidia cards. --->PCIe 5.0 PSUs are the optimal choice for the latest gaming graphics cards with PCIe 5.0 support. PSUs with this standard come with a 12VHPWR (12 Volt High Power) connector out of the box and do not require a separate adapter cable.