X-bit labs

Roundup: 14 Power Supply Units from Thermaltake (page 10)

Category: Other

by Oleg Artamonov

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

PurePower 680APD (W0049 rev. 2, 680W)

When I was testing the first revision of the W0049 power supply I found that its parameters were quite different to what the Thermaltake website said, although it didn’t mention a release of a new version of the PSU. Moreover, we took the sample from a retail shop, so the explanation that I was dealing with an engineering sample didn’t work. So, we contacted Thermaltake and they were kind to offer us a sample of the W0049 model whose characteristics coincided with the specification you can find at their website.

The PSUs are very much alike on the outside: two fans and a shiny dark case. The single difference is that the newer version has no vent holes in the side panel (it is the panel the label is attached to).

The internal design of this PSU is dramatically different from the previous revision, but it is made by Sirtec, too.

There is a PCB on the heatsinks here, too, but it now carries the low-power section of the PSU electronics (a regulator controller and fan speed controller) rather than an additional regulator. Such PCBs are often installed in perpendicular to the main PCB, but it would collide with the second fan here, so they had to place it at the top. You can see it even in the snapshot that there are no power elements on it (remember the couple of diode packs in the previous PSU?).

The additional PCB is connected to the main one with two groups of contacts.

The PSU follows the classic circuit design with group voltage regulation. Although it has three +12V lines, like the first revision, there is only one +12V source inside it. Then, there are also three shunts and a circuit that controls the passing current. As a result, we’ve got three “virtual” +12V lines that only differ in the over-current protection thresholds.

Some readers have inquired if it’s necessary to load all the three +12V lines for the PSU to work normally. Well, it’s clear that these lines converge into one inside the PSU, so there’s absolutely no difference between putting a load of 4A on both +12V1 and +12V2 lines and putting a 8A load on only one of them and not using the other at all.

In comparison with the previous revision, the allowable load on the +5V line is reduced to 30A (because this PSU was designed from scratch rather than redesigned out of an older model; today, there is just no sense in developing a PSU that allows high consumption from the +5V output), but the total load on the +12V lines can be as high as 52A (624W, which is just a little short of the PSU’s full output power). These changes in the specification are the most noticeable external difference between the first and second revision of the W0049.

The PSU offers the following cables and connectors:

• A mainboard power cable with a 20+4-pin connector, 56cm long
• A CPU power cable with a 4+4-pin connector, 56cm long
• Two cables with 6-pin graphics card power connectors, 56cm
• One cable with two Molex connectors, 55cm+20cm
• Two cables with three Molex connectors and one floppy mini-plug on each, 56cm to the first connector and 20cm more to each next one
• Two cables with two SATA power connectors on each, 56cm+19cm
• Two fan power cables with 4-pin Molex connectors, 55cm
• A cable with an output of the velocity sensor in one of the PSU fans

The connectors for additional fans serve an obvious purpose: they are connected to the PSU’s fan speed controller and thus give you an option of automatic adjustment of the speed of all the system fans. What is not quite clear to me is why they have 4-pin Molex connectors. The user will have to search for adapters because an absolute majority of fans have small 3-pin connectors.