Seasonic Super Tornado 300 ATX12V v1.3 PSU

Viewing page 2 of 5 pages. Previous 1 2 3 4 5 Next


The sample came with the usual power cord, 4 mounting screws, a multi-page manual, a warranty card, and the "Dr. Cable" cable management kit. The basic appearance of the Seasonic Super Tornado 300 is not much different from other 120mm fan PSUs such as the recently reviewed Fortron-Source Aurora.

Note the absence of a 110-220VAC switch in the photo above. The photo below shows the PSU from behind, upside down. All the intake air vents are visible. There are very few vents other than the back exhaust panel. This ensures that most of the air from the fan is blown out the exhaust on the other side. One can only conjecture that the few slots visible on the back and sides might provide some level of airflow around hot components on the other side of the slots.

Cables & Connectors - There are 7 wire sets. The longest cables are long enough to reach just about anywhere even in a full tower case, and 8 Molex 4-pin connectors are probably enough for fully loaded PCs. Serial ATA power connectors or adapter are not provided.

  • 2 cables, 33" long, each with three 4-pin IDE drive connectors and 1 floppy drive connector
  • 1 cable, 19" long, with two 4-pin IDE drive connectors
  • 1 cable, 19" long, with main 20-pin ATX connector
  • 1 cable, 23" long, for 12V (P4) connector
  • 1 cable, 23" long, for 3.3V connector
  • 1 cable, 23" long, for PSU fan RPM monitoring (3-pin motherboard header)

Opening the cover exposes modest size heatsinks with a geometry that seems well optimized to maximize surface area, and a clean, uncluttered layout. As with the Super Silencer 400, the top and bottom halves of the PSU fit very snugly. There is, BTW, a little paper label over one of the screws that hold the cover on which states WARRANTY VOID IF REMOVED.

The fan is a "SuperRed" 120mm ball bearing model CHB12012AS-A rated for 12VDC and 0.19A current made in China by Cheng Home Electronics Co Ltd. This is the same brand used in the Super Silencer 400. The company is based in Taiwan, according to their web site. Seasonic says this fan has an airflow rating in free air of a massive 61 CFM and a noise level of <35 dBA (presumably at 1 meter).

This view above shows the 3-pin plug to the 120mm fan, which has RPM monitoring. One 220uF 400VDC capacitor is used for the full range Active PFC circuit. BTW, the exhaust grill panel did get bent a bit while being handled; it was easy to straighten it out before putting the cover back on.

Like in the Super Silencer 400, an unusual aspect of the fan circuitry is that its ground is isolated from the rest of the PSU, apparently to ensure that the fan voltage does not sag even with high loads on the main output lines. Normally, only the positive voltage lead to the fan needs to be tapped; the negative voltage can be read from any black lead on any output connector, a 4-pin Molex being the most convenient. Not so here. Both positive and negative leads to the fan had to be tapped to measure the fan voltage.


The Seasonic Super Tornado 300 is the second PSU we've seen that is compliant with Intel's ATX12V Version 1.3 Power Supply Design Guide released a few months ago. (See details in SPCR's Recommended PSUs article.) The first was the Seasonic Super Silencer 400. One of the changes from version 1.2 to 1.3 is the removal of the –5V rail. It is no longer required, and Seasonic's Super family does not provide it. Apparently its absence does not cause any conflict with recent motherboards produced prior to the v1.3 guide.

The specifications here come from a technical Seasonic document (EA-V30FB01-4: Jul 10, 2003) that provides a lot of detail. Some of the information here contradicts slightly the info in their product brochures and retail box.

Efficiency, for example, is cited in this document as >74% at full power output with 120VAC and >77% at full power output with 240VAC. This is substantially lower than the 78% and 80% cited in the marketing materials.

Note the high current 18A capacity of the 12V line. This is one of the most significant changes in the ATX12V guidelines from V1.2 to V1.3.

Output Capacity:

AC Input
AC Input 100-240V ~7A 50/60 Hz
VDC Lines
Voltage Regulation
Max Current (peak*)
18A (20A)
2A (2.5A)
Max Output
Total Output
300W (340W peak*)

*Peak minimum duration 1 second

4-in-1 Protection: Over voltage / over power / over temperature / short circuit protection. One presumes all of these conditions will cause the PSU to shut itself down.

Operating Temperature: 0 to 50° C. Relative humidity: 20% to 80%. The rated power will reduce from 100% to 80% from 40° C to 50° C linearly.

MTBF (mean time between failure): Typically over 100,000 hours at 25° C under full load, excluding the DC fan.

There are 13 logos for safety and EMC approvals:

Previous 1 2 3 4 5 Next

Power - Article Index
Help support this site, buy from one of our affiliate retailers!