X-bit labs

Roundup: 14 Power Supply Units from Thermaltake (page 7)

Category: Other

by Oleg Artamonov

[ 07/28/2006 | 08:34 AM ]

PurePower 560APD (W0023, 560W)

The W0023 differs dramatically from the previous model. It has a black case (the paint isn’t glossy, but matte; it even feels coarse to the touch). There are no LEDs here, no transparent windows, no decorations, only a large sticker Xaser on the side panel. You should be aware that the protruding grid of the fan on the top of the case may prove to be a problem when you try to install this PSU into certain system cases.

The internal design of this power supply has nothing to do with the W0020, either. The actual manufacturer of the PurePower 560APD is Seventeam Electronics as is indicated by the marking on the filter card (soldered to the mains connector) and on the main PCB of the power supply. The original name of this model is ST-522HLP.

The most unusual thing about this PSU is its heatsinks which are copper bars with aluminum ribs. Otherwise, we’ve got an ordinary enough design with active PFC and group voltage regulation. An ML4800CP chip is used as the main controller here (it combines a PFC controller with a switching power controller proper). An additional PS222S chip protects the output voltages and currents from overshoot.

The PSU label claims a peak output power of 600 watts but doesn’t specify the conditions under which it is achievable. The name and the official specification of the product imply a maximum output power of 560W (not peak, but sustained). The marking on the PCB reads “Seventeam ST-522HLP”, thus suggesting an output power of only 520W. Anyway, I checked this unit out under a load of 525W and it easily passed through the tests.

The PurePower 560APD surpasses the previous two models in the declared load currents, but doesn’t go too far beyond the ATX12V 1.3 specification with its allowable load of only 22A (264W) on the +12V rail, which is far lower than ATX12V 2.0 units offer.

The PurePower 560APD has the following cables and connectors:

• One cable with a 20-pin ATX connector (58cm)
• One cable with a 6-pin AUX connector (it looks like one half of the AT power connector, which was used on some mainboards, mostly with support for Rambus memory, and was eventually discarded as unnecessary in the ATX12V 2.0 standard; the cable is 52cm long)
• One cable with a 4-pin ATX12V CPU power connector (59cm)
• Four cables with two Molex connectors and one floppy mini-plug on each (57cm from the PSU case to the first connector and 15cm more to each next connector)
• One cable with two SATA power connectors (40cm+20cm)
• A cable with a fan speed sensor (50cm)

All the cables, except for the latter, are sleeved and painted different colors: black for the main mainboard power cable, red for the AUX and ATX12V cables, blue for the PATA cable, and green for the SATA cable.

The cross-load diagram of this PSU is not ideal, but acceptable. It’s only at high loads on the +5V and +3.3V rails, i.e. in a very unlikely situation for a modern computer system, that the voltages violate the limits described in the ATX standard as acceptable. If the load distribution is typical (a total of 25-50W on the +5V and +3.3, and 50W and higher on the +12V rail), the voltages are all rather close to their nominal values.

At a load of 525W the high-frequency voltage ripple is 57 millivolts on the +5V rail and 42 millivolts on the +12V rail. If you sum this up with the low-frequency pulsation, the voltage ripple is 71 millivolts on the +5V and 54 millivolts on the +12V rail. I want to remind you that the maximum allowable voltage ripple is 50 millivolts on the +5V and +3.3V rails and 120 millivolts on the +12V rail. It means the PSU doesn’t comply with the requirements of the industry standard when working at full load.

But if the load is reduced to 100W on the +5V and to 20W on the +3.3V rail (this gives you a total load on the PSU of a little lower than 400W), the ripple diminishes to 25 millivolts on the +5V and to 15 millivolts on the +12V (although the load on this rail remains the same). I want to again recall the fact that modern computers do not load the low-voltage rails much, so the problem with the strong pulsation of the output voltages isn’t going to show up in practice, but this is just an excuse, of course. The PurePower 560APD was developed to comply with the ATX12V 1.3 standard and must provide the required parameters without any allowances for the changes in power consumption of computers that have occurred after the standard was accepted.

A Sunon KD1209PTB1 fan is installed on the top panel of the PSU, and a Sunon KD1208PTB1 is placed at the back panel. The speed of the fans is varied depending on the temperature. There’s no means of manual control – you can only use the mainboard’s tools to monitor the speed. The PSU is not silent, but rather quiet. The speed of the fans doesn’t change at all at loads below 200W, but then begins to grow up linearly. The sound of the fans becomes annoying only when the load approaches 400W.

The PSU efficiency is average at 80%. The power factor is 0.99 at the maximum as is normal for power supplies with active power factor correction.

The W0023 doesn’t look an appealing buy to me. This power supply exceeds by just a little the requirements of the obsolete ATX12V 1.3 standard, and in such cases you should consider the allowable current on the +12V rail rather than the total wattage of a unit. Here, we’ve got 22A or 264W. It means that in a modern computer that consumes most of its power from the +12V rail the maximum allowable load on the PSU will be not 560W but 264W plus 30-40W more on the low-voltage rails. That is, about 300 watts in total. So, if you are comparing the W0023 with newer power supplies, you should regard it as a 300W unit. Well, an absolute majority of home computers will be quite satisfied with 300 watts of power, but the price of a power supply depends directly on its specified wattage. It means the W0023 is rather expensive in comparison with new ATX12V 2.0 units, yet there is no sense in this overpayment.