When I was replacing my main desktop PC a couple of years ago, I decided to go for a custom-built machine rather than an off-the-shelf design as I had reasonably firm ideas about what I wanted and nothing really appealed to me from the big manufacturers' ranges. Some of the components I found very easy to order; I'd fitted any number of graphics cards in my time, for example, so had a good idea what I was looking for there. The power supply, though, was a different matter, and I made my head ache doing the research on that. It was worth it in the end, though, as it turns out that I made a super choice in the Corsair VX450W.
There is a lot of nonsense talked about power supply units. To read some of the more excitable websites in particular, you'd think that if the wattage of your PSU isn't in four figures then you're at imminent risk of blowing up your computer. This, to be blunt, is complete nonsense. The problem is that a lot - and I mean a *lot* - of power supplies are of pretty poor quality, and are not really capable of operating at anywhere close to their rated values with any degree of reliability at all: there are plenty of so-called "600 watt" units out there that struggle to deal with much more than half of that power. It's disgraceful, but unfortunately it's been the case for a long time now. Hence the need for the aforementioned research!
Given the above, and how vital the PSU is to your PC for pretty obvious reasons, this really isn't a component on which to skimp unless you enjoy regular overheating, system freezes or even perhaps damage to other parts of the computer. A good 450 watt unit will prove much more dependable than a poor 650 watt one, and Corsair have had a (deservedly) excellent reputation for reliability for some time now. They wouldn't be offering the five-year guarantee that they do unless they were pretty confident in the quality of their products, and although there's some way to go I really don't think that, even if my PC lasts five years, it will be this PSU that fails first. Not unless I go mad and start attacking it with a hammer, anyway, and maybe not even then!
The VX450W is a low-end unit by Corsair's standards, but nevertheless it's nicely presented, even down to a little cloth bag branded with the company's logo. I certainly didn't get the impression that they were cutting any corners, and that added to the sense of reassurance I'd already received from reading other people's experiences of the brand. The cables are of a pleasingly good length, which makes fitting it easy no matter what the layout of your case. They aren't modular, though, which means that you will need somewhere out of the way inside the case to keep those that you don't need. That shouldn't be a big problem for most, though. What might be is that you only get one PCIe connector, so you can't (without adapters, anyway) use graphics cards that need multiple inputs, or run two cards at once. This unit isn't really aimed at power gamers, though, and the restriction is not a big problem for low to mid-range systems.
When this power supply appeared, there was some discussion about Corsair's decision to provide a single +12V rail, rather than several. The reason was that, since this particular rail is rated for a total of 33 amps, and therefore 12 * 33 = 396 watts, that meant that it was in violation of the (now changed) Intel ATX guidance that no single rail should carry more than 240. Corsair contended that having a single rail was better, since then all spare power could be used - on a multi-rail system, if you have a 12A rail and a component draws 8A, the other 4A is "trapped", whereas with a single-rail system it's all available for use elsewhere. I'm with Corsair on this one, I think; certainly my power supply hasn't had one single flicker of a problem in two years of quite hard use.
This is a very quiet power supply. So quiet, in fact, that at first I was a little bit concerned that it wasn't even on, and had to check it specifically to be sure! It's not quite the utter silence that some of the more gushing reviews claimed, but even so it's very impressive; the whirr of even an ordinary case fan pretty much drowns it out. That makes this a good choice of PSU for quiet environments; if your PC is in your bedroom, for example. It's also pleasingly efficient: Corsair claim 85% at a modest 220W power draw, and most of the specialist reviews I've seen consider that not to be a huge exaggeration. Many lesser units only manage 70%, if that - and since better efficiency is good for both the environment and your pocket, it's another plus point.
Oddly enough, the only slight problem with the VX450W (aside, of course, from its unsuitability for power-hungry, cutting-edge PCs) is the thing that made it such a good buy in the first place: its price. Whether it's to do with the depreciating pound or whether the cost of capacitors has increased (they're high-quality Japanese ones, incidentally, another thing you won't get with a cheapo PSU) I don't know, but this power supply will now set you back not far short of £60, whereas I got it for about £10 less. I would happily have paid the extra tenner, however. I've been extremely happy with this unit, have had no problems whatsoever, and will be looking at Corsair first whenever I next need a PSU. Absolutely recommended.