X-bit labs

ATX Power Supply Units Roundup. Part IV (page 10)

Category: Other

by Oleg Artamonov

[ 04/10/2006 | 09:02 AM ]

The PSU offers the following cables and connectors:

• Mainboard cable with a 24-pin connector (with a detachable 4-pin part); 47cm
• CPU cable with an 8-pin EPS12V connector; 49cm
• CPU cable with a 4-pin ATX12V connector; 50cm
• Two graphics card cables with 6-pin connectors; 50cm
• Two cables with four Molex connectors an one floppy mini-plug on each; 50cm to the first plug and 15cm to each next plug
• Two cables with two SATA power connectors on each; 61cm+15cm

Instead of separate wires, we have flat silver cables here. The manufacturer claims such cables help to maintain proper airflows inside the system case, but I doubt that airflows can be affected much by a simple change of the shape of cables. I think the main advantage of FlexForce cables, as they are officially dubbed, is of an aesthetic nature. They do have drawbacks, by the way. First, you may find the lack of color-coding of the wires inconvenient. And second, a flat cable can be bent in one direction only, so you may have some troubles trying to lay them out neatly in the case.

The cross-load characteristic of this PSU is average. On one hand, the diagram covers almost the entire range of loads allowable for this model, but on the other hand, all the three voltages vary greatly and deflect rather far from their nominal values under loads typical of modern computers.

At a load of 475W the voltage ripple was 40, 85, 26 millivolts on the +5, +12, +3.3V rail, respectively. A low-frequency, 100Hz constituent accounts for the most of the pulsation.

The fan speed management system works rather oddly in this power supply. The speed is altogether constant at 1000rpm under loads of below 150W. It then grows up quickly under higher loads, reaching 2100rpm. As a result, the PSU is quiet under small loads, but audible under a load of 250-300W. Moreover, the plastic sheet that partially covers the fan rattles as in some other power supplies from Wintech. To solve this problem, tighten the screws that hold the sheet and add a few drops of glue – or just remove that piece of plastic altogether!

The PSU is 81% efficient at best, which is a good, but not record-breaking result. The power factor varies from 0.65 to 0.67 (as I said above, this unit lacks any type of power factor correction).

The X-Finity ULT-FX500 has done as well in my tests as the other Wintech units I’ve met. It is an average-quality product without any serious advantages, but with acceptable parameters. The drawbacks of the ULT-XF500 in particular are a strong 100Hz output ripple, lack of any type of power factor correction, and a rapid increase of the fan speed at higher loads, which makes the PSU rather noisy. If these drawbacks do not disturb you, you may be pleased with the ULT-FX500, which is a good enough modern power supply.