Previous leaks had already suggested it: MSI was the first manufacturer to introduce power supplies based on the new ATX 3.0 specification. Both feature one of the new 12VHPWR connectors with 12+4 pins according to PCIe 5.0 for up to 600 watts, up to 2,600 watts can be supplied to the system for a short time.
This is behind ATX 3.0
ATX 3.0 was developed under the direction of Intel and replaces ATX 2.x after nearly 20 years. In addition to the specifications for the adaptation of Alternate Low Power Mode (ALPM), as used by Windows 10 and Windows 11 in Modern Standby, ATX 3.0 has a particular goal: to reliably supply more powerful hardware with higher power consumption. , even if the system calls back significantly more than the official TDP of the components would suggest.
ATX 3.0 takes into account load peaks
ATX 2.x has so far ignored this case. Whether load spikes above the rated power could be absorbed by an ATX 2.x power supply depended on the power supply, not its ATX compliance. That could lead to big problems. A prominent example from the recent past is the issues with the GeForce RTX 3000 launch in late 2020. However, users should also be familiar with other scenarios for the system shutting down or becoming unstable, although the source feed must be strong enough on the paper.
Specifically, ATX 3.0 stipulates that power supplies must be able to provide up to 200 percent of their rated power. This applies to models with more than 450 watts and/or with the new P12VHPWR connector for graphics cards. Models with a maximum of 450 watts and/or without connection P12VHPWR must deliver a maximum of 150 percent of the nominal power.
Three specific examples are intended to make what the specifications say more understandable:
- A power supply with 1,000 watts and P12VHPWR should be able to deliver 1,000 watts continuously, but up to 2,000 watts to the system for short periods of less than a maximum of 100 µs during 10 percent of usage time. It must be possible to deliver 1,600 watts for a maximum of 10 µs during a maximum of 25 percent of the time of use.
- A 300-watt power supply without P12VHPWR should deliver up to 450 watts for a maximum of 100 µs for a maximum of 10 percent of usage time.
- A 300-watt power supply with P12VHPWR should deliver up to 600 watts for a maximum of 100 µs for a maximum of 10 percent of usage time.
This is how peak loads are tested
Manufacturers must demonstrate this maximum load resistance by testing the respective deflection scenario with a properly adjusted “normal” load between the maximum loads. Therefore, a 1000-watt power supply must be able to support a load of 2000 watts for 100 µs (10 percent) and a subsequent “silent phase” with 817 watts for 900 µs (90 percent), which in root mean square is 1000 watts and therefore the power rating is equivalent to.
PCIe 5.0: Up to 3 × 600 watts for graphics cards
The standard makes it clear: The fact that an ATX 3.0 power supply uses the new P12VHPWR connector defined by PCI Express 5.0 has a decisive influence on how high the short-term deviation from rated output should be.
The background is that PCI Express 5.0 for the first time defined deviations from the nominal power consumption of the graphics card via P12VHPWR. In this case it is up to 300 percent. In other words: a graphics card that draws its power from the P12VHPWR with 12+4 pins may briefly consume three times as much power as its TDP suggests. With a maximum of 600 watts defined across P12VHPWR, this means that the power supply must be able to deliver up to 1,800 watts through the connector, for up to 100 µs long periods.
For intervals between more than 100 µs and one second, it should be possible to exceed the nominal power by up to 300 percent, with the following mathematical relationship between the maximum power (R) and the duration of the interval (T) in microseconds:
R = 4 – 0.2171 x ln(T)
MSI MEG Ai1000P and Ai1300P
The first officially introduced ATX 3.0 power supplies adhere to these specifications. MSI MEG Ai1000P Y MSI MEG Ai1300P thus, they can officially deliver up to 2,000 watts or up to 2,600 watts to the system at maximum 100 µs intervals, of which up to 1,800 watts to the connected graphics card via P12VHPWR. The manufacturer provides the corresponding proof in the blog post for the presentation and meets the standard conformance test required by ATX 3.0 in an exemplary manner.
Both power supplies have the new P12VHPWR connection with 12 current pins and four sensors, the assignment of which tells the graphics card that it can draw up to 600 watts continuously, and thus up to 1,800 watts peak load from the power supply. feeding.
Previously available ATX 2.x power supplies, for which there is a pin X × 8 to P12VHPWR adapter, give the graphics card the “ok” via the cable itself. For example, Asus coded the adapter for ROG Thor Platinum II in such a way that the graphics card”up to 600 watts is ok“he pointed.
Nvidia is supposed to build on the new connector for the GeForce RTX 4000 like it did for the GeForce RTX 3090 Ti. No information about the Radeon RX 7000 is known to date.
The manufacturer has not yet commented on prices and dates. Product pages too. MSI MEG Ai1000P Y MSI MEG Ai1300P they are already online.