This is the first ATX 3.0 compatible SFX PSU that falls into my hands, I couldn't let the opportunity pass and not present it to you. CWT was kind enough to allow me to post a review and show you what to expect from the upcoming generation of PSUs. After the changes in light-load efficiency, Intel forces all manufacturers to improve their products' transient performance, of immense importance. Dynamic loads are the daily routine for every PSU, so the performance with transient loads represents with high accuracy how a PSU will do in real-life scenarios. The Nvidia RTX 3000 series caused several problems in some of the existing PSUs, forcing Intel to raise the bar too high (in my opinion), asking ATX 3.0 PSUs to operate without problems at up to 200% transient loads. This can cause issues in the protection features circuit, designed to protect the PSU from overloads, and can lead to catastrophic results, so it is not easy to build a PCIe 5.0 ready PSU meeting the Intel ATX 3.0 specs requirements.

For those who are not highly familiar with PCIe 5.0 and ATX 3.0, a PCIe 5.0 PSU is not necessarily ATX 3.0 ready since, besides power excursions, ATX 3.0 has several more requirements. On the other hand, an ATX 3.0 compatible PSU is always PCIe 5.0 ready. I cannot be sure if the extreme demands of ATX 3.0 when it comes to power excursions will be required once the new GPUs surface. It would be highly preferable to push the GPU manufacturers to fix the power spike issues on their products rather than pushing PSU manufacturers so hard. Still, Nvidia and AMD have more influence than PSU manufacturers, and Intel couldn't force the first to improve their products. That said, until the new graphics cards with PCIe 5.0 connectors become available, nobody can be sure if the strict ATX 3.0 requirements are a necessary or unnecessary headache for manufacturers. So far, several OEMs have chosen the easy way to adjust OCP at +12 V and OPP too high to cope with power spikes, rendering essential protection features useless. This is a potentially dangerous way to cope with power spikes, but there is no other (affordable) way to make older platforms compatible with demanding GPUs.

The CWT CSX850M-G is a fine unit and the first SFX PSU I have permission to show publicly, offering ATX 3.0 support. More examples will arrive from other OEMs, increasing the competition in this form factor. Currently, nobody is certain when the new Nvidia GPUs will be released, but once they do, I will have many PSUs to test, checking if the ATX 3.0 power excursion requirements are necessary or overkill.