I need to replace a 350W power supply in a computer my dad gave me when he bought a new one. I was looking online and power supplies seem to range from $25 to $70.
Do I need to worry about the voltage on a power supply, or as long as I but a 350W one, it’ll work? Can anyone recommend a good one?
if it’s really cheap, it’s crap. the voltages are standard for any ATX supply, so no real need to worry about that. I usually won’t pay less than $50 for a power supply of 350-500 watts output. I typically use Antec supplies but other people seem to have had issues with them. I haven’t.
I’m actually expecting a Corsair HX 750 today to replace an Antec TruePower II. I used to use Antec exclusively (cases and PSUs), but have had three failures in a relatively recent span of a couple years. Different PSUs in different machines. Bad luck perhaps, but between that and a few minor changes in case construction (super-nitpick, but my newer cases don’t have those stay-in-place screws anymore) I’ve lost a bit of faith. The Corsair had excellent reviews, is modular, and has extra long cables for this particular machine.
To the OP, there are a plethora of vague errors that can be sourced to a power supply. Not just a dead unit, but too much voltage fluctuation (I think that’s the right term) can lead to anything from random, intermittent restarts to blue screens. Go to newegg.com and check reviews before buying. The price difference doesn’t have to be astronomical, but be careful that others’ experiences with the unit you go with have been positive. Not that there are any products without some negative reviews, but saving $20-$40 may cause more headaches than it’s worth. (I underlined ‘may’ because a cheap PSU won’t *necessarily *cause problems).
This one has a ton of good reviews and is only $30, but to me, it just looks cheap and obsolete. Any experiences with Rosewill?
I may just go with the Corsair if that’s what people are suggesting.
the problem with reviews on an e-store’s site is that people seem to post their review right after they get the part, but I’m not sure if too many think to go back and update it if the thing dies within a year.
But yeah, that Rosewill looks a bit skeevy. The Corsair Rhythmdvl linked is a good quality supply, but it’s way WAY more than you need. if you’re replacing a 350 you definitely don’t need 750.
this might be suitable:
Fortron-Source (FSP) is generally one of the better-regarded brands and AFAIK they actually manufacture power supplies.
How old is the motherboard it’s powering? The PSU you linked to is a 20-pin, not a more modern 24-pin.
For reliability and quality, I’d suggest any one of the following brands:
Corsair
Antec
CoolerMaster (that’s the one I currently have)
PC Power and Cooling
Zalman
PSUs basically have five or so criteria for buying them. The first is general build quality. Good units use quality Japanese capacitors, good bearings in their fans and all that other stuff that keeps things from exploding. Those quality parts also impact on the efficiency, voltage drop, and ripple of the unit. The more efficient the drive, the less power it’ll draw from the wall to generate the 380W (or whatever). Less power means less heat and less cooling necessary. Less heat means it’s less likely to die. Most drives are 80%+ [some grade.] The grades are Bronze, Silver, Gold, Platinum. Bronze is 81%ish. Silver is lower-mid 80s. Gold is upper-mid 80s. Platinum is basically 89 or higher. Those may not be the official numbers, but it’s close enough. Anyway, voltage drop means you may not get enough juice on a line to power your stuff. That’s bad. Too much ripple will cause malfunctions and destroy stuff. The final criteria for buying a PSU is basically features. Some are modular, which keeps unnecessary cables from getting in your way when servicing the case or impeding airflow. Some PSUs are fanless which decreases noise.
I was going through low wattage PSUs for another thread and the Seasonic S12II 380W stood out as an excellent unit for $55. Newegg reviews don’t mean anything for PSUs. The only people to listen to are those who can afford a load tester, like the websites anandtech, jonnyguru and silentpc. More PSUs exist than reviews, so if a unit isn’t covered, a general rule is that PC Power & Cooling, FSP, and Seasonic are the best.
Agreed. My experiences with Antec may just be my mileage varying, but I’m superstitious like that. As I said, I have a lot of Antec boxes and PSUs in here, so I’ve trusted them for a long time.
I have a good handful of Rosewill components (e.g., external HDD enclosures, card readers) and haven’t had issues. But none of them are critical components, so my experience is limited.
to be fair, they’ve had a few models that were widely known as turkeys but I can’t think of which ones specifically. IIRC the original Smartpower series had longevity issues; I think I just managed to avoid the troublesome ones.
I was warned against buying a Rosewill once and went ahead anyway. It died within a half hour in the machine.
Some Antec PSUs are basically Seasonic PSUs, which are good. Some are… uh… someone else and they suck. I know Antec EarthWatt is Seasonic’s cheaper line.
I currently have a Corsair 700W running my TV/media server computer 24/7 and it has not caused me any problems since I started running it 3 months ago. I chose this brand because of a Black Friday sale.
My previous brand was FSP and I only got it because it was on sale and it actually ran for 2-3 years 24/7 with no problems.
Well there was a small problem in that the FSP was some case modder’s PSU and had this blaring blue light in it that shone out of all the holes in my case like the Second Coming was going on inside 
I see a lot of firms marketing Japanese capacitors, but have no idea why they’re better. Any insight?
The rest of the post is great detail. I have a PSU tester, but it’s just a glorified (and easy to use) voltmeter. It tells if the PSU is dead or not, and if monitored for a long time (never saw one that keeps logs or that can be kept plugged in for a while) it can give insight into fluctuation, but as Palooka says, unless it’s testing under load it’s only checking part of the PSU’s integrity.
I’m not sure reviews are completely meaningless–patterns evolve and it can be a quick way of separating known problems and issues. In addition, it’s a collection of feedback on what’s actually available without searching for reviews on each and every PSU under consideration. I’ve found this particularly helpful in finding a unit with longer cables–some complaints about barely fitting into a mid-sized case told me that unit wasn’t right for the machine I was working on.
Cheap Chinese and Indian capacitors aren’t sealed very well so the electrolyte dries out which causes the capacitors to dry out. When that happens, it increases the electric noise, which translates into higher voltage drop and ripple. When it gets bad enough, the PSU dies or your computer dies. The Japanese ones are well-made so the seals don’t leak. Also, sometimes the Chinese ones are just faked by having a low-rated capacitor instead a higher-rated case.
Cheap power supplies can be rather optimistic in their ratings, to be kind. For example, one might have a 500w rating. But that’s calculated by figuring how much wattage each rail (12v, 5v, 3.3v, etc.) can supply on its own, under ideal conditions. In actuality, with power drawn from all rails, the power supply might only be able to reliably supply 150-250 W. Ask more than that and the cheap-and-nasty power supply might become flaky, die an early death, or damage your components.
Mostly a bad power supply can just make your computer unreliable, and cause intermittent crashes or hangs. Something that infrequent can be absolutely infuriating (one crash every day or two will still stop you in your tracks and destroy your work) but hard to troubleshoot.
But cheap power supply manufacturers get away with this because most people really don’t use more than 150 watts – that’s all you need for a hard drive, a processor, and a couple other miscellaneous bits, even with everything running flat out. And most of the time, general-purpose web browsing and office tasks don’t consume anywhere near that much power.
It’s the gamers and computer geeks (like some in this thread) who have to feed lots of power to overclocked processors, power hungry graphics card(s), and large collections of hard disks. That can quickly add up to 500 W or more.
Rosewill is Newegg’s house brand. It’s ok, nothing special, but IME they’re not dangerously poor quality. I have a 550W rosewill PSU that’s been fairly reliably running my desktop for about four years. Of course (until some recent upgrades) that desktop probably consumed no more than 300W.
The computer is 3-4 years old. I plan to connect it to my LCD TV using a DVI-to-HDMI cable. I didn’t realize the Rosewill I mentioned was only 20-pin.
The Corsair was a bit too pricey for me. The FSP looks good, but a couple of people complained in the review that the cables are too short. The computer I’ll be putting it in is an HP Pavilion tower, so I’ll need longer cables.
If other people can also recommend the FSP ZipperJJ suggested, I’ll go with it.
BTW, where does the term “rail” come from and what does it mean? I know what it is in the general sense, but have always been curious as to its origins and a more technical definition.
Another thing to check–how are you getting sound? Some video cards need a proprietary DVI-HDMI adapter to get sound output, some video cards won’t put out any sound at all, and some won’t have any problems.
(I have an MSI 4800 in our HTPC. It requires an MSI adapter. When I found out and contacted them about buying one, they sent it for free. Excellent service!)
Funny thing. I was thinking about that as I made my last post. I’m not sure how sound’s going to work yet. I guess I’ll see first if the video card does any sound.