Nah, 12 years is nothing for a good quality power supply, it's really only after 20 years or so that you could start to have any significant degradation. That of course does not apply to cheapy PSUs or ones that have been run overly hot, but you shouldn't have either scenario with an old Dell... they were pretty well built overall.

I had a Dell 4100 back when. It was one of the good dells, and everything in it is pretty much bulletproof- I wouldn't worry bout the psu.

Sometimes the fan bearing/bushing will wear out.

I had a 1999 PC Power & Cooling Turbocool 300W until a year ago. I finally retired it because it was becoming increasingly noisy (inductor whine I believe). I had put that PSU through various forms of hell though.

A bad fan is easy enough to replace, and a drop of nail polish or a bit of heatshrink tubing does wonders for inductor whine.

The older Dell PSUs usually had Minebea or Superred fans with ball bearings which were pretty reliable to begin with, and they were also usually temperature controlled, so they rarely ran full speed... occasionally I've come across a worn out one, but it's pretty rare even on 10+ year old units.

sgt76 wrote:

I had a Dell 4100 back when. It was one of the good dells, and everything in it is pretty much bulletproof- I wouldn't worry bout the psu.

I agree. I have a Dell Dimension 4100 somewhere in storage, and it's easily one of the best Dells, if not one of the best Pentium III boxes I've ever used. 😀

Old Thrashbarg wrote:

A bad fan is easy enough to replace, and a drop of nail polish or a bit of heatshrink tubing does wonders for inductor whine.

That's not really a solution, is it? The reason these things start whining is because your caps are failing 😉

Not necessarily. Failing capacitors can aggravate the problem in a few different ways, but they don't always cause the problem.

A lot of those inductors are just wire wrapped around a ferrite core without any potting, or with just a little bit of glue. The ferrite core will vibrate a certain amount when there's current passing through the coil... most of the time the movement microscopic enough that you can't hear it, but sometimes after years of use the glue can degrade or the wire can loosen a bit, allowing the core to vibrate more, causing an audible sound.

Making a PSU work constantly at its limits will kill it, always leave some headroom!
If you kept the machine stock (or close) the PSU is probably fine.
But if you have upgraded the video card and installed 4 more hard drives...take a multimeter to the PSU while the PC is running, or run some hardware monitoring utility that lets you see if the voltages are where they should be. At least it will give you peace of mind.

If anyone here plans on replacing a fan, remember to be careful about what you touch inside of a PSU. Those big caps can hold a dangerous charge.

btw, most noisy fans can be easily fixed with some engine oil.

Use vaccination syringe (the one with the shortest needle). The bearing you need to lube is usually under the sticker. If you use a quality psu, it should be covered with rubber (one more way to find out how cool your psu actually is). Put a small drop on a bearing, then rotate the fan. You can put one more drop after that if you wish.

So, there is no need to replace the fan each time it gets noisy. This way is easier and does not require any soldering job to be done. However, it won't help if your fan is unbalanced (sounds like rrrRRRRRRRrrrrr) 😁

Oiling works OK on sleeve bearing fans as long as the bearing isn't terribly worn/damaged, but it's not so good on ball-bearing models since it's quite difficult to get much lubrication down inside the bearings (and some of 'em are actually sealed bearings, so you can't get any oil into 'em).

It's also possible to replace the bearings in a fan, since they pretty much all use one of two or three different standard sizes of bearings. That approach is usually not worth the effort, though, unless it's an unusual size/shape fan that can't easily be replaced. I've had to do it a couple times on oddball laptop and graphics card coolers.

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With regards to disassembly of a PSU... of course with all electrical devices you should always be careful, however, just to head off the usual misconceptions that seem to come up whenever this sort of topic is discussed:

I've never seen a computer PSU-- even a cheap one-- that didn't have bleeder resistors on the main caps to discharge 'em when the unit is unplugged. Those resistors almost never fail, since they have very little current ever passing through them. And even if they were absent or failed, the charge would still be drained fairly quickly just by the losses through the rest of the PSU circuit.

As for how long it takes to discharge the caps, I did some tests on a dozen or so PSUs awhile back, specifically to come up with an answer to that... and it seems to usually take about 10-15 seconds for everything to discharge in an average ATX power supply, though I had a higher wattage one with enormous primaries that took closer to 30. It takes me at least a full minute to get the cover off one, and even with the cover off many PSUs are designed such that it's quite difficult to touch any metal on the mains side without pulling the board out. So realistically, even if you already had the PSU out on your bench and decided to start working on it immediately after unplugging it, it's extremely unlikely you'd ever be in any danger.

Thanks for all the great replies, very helpful! It's nice to know that these dells are built well, I owned a 4100 when they were new, and I also owned the earlier series, an XPS D266.

As with cars it's less about the age and more about the mileage. Keeping dust out of the fans will help too, as dust will wear out the fans and potentially allow the PSU to overheat.

I've had multiple PSUs fail over the years, and they rarely damage the computers they're connected to. This is because their failure mode seems to most commonly be to supply less and less voltage (or to suddenly die and deliver none at all), starving the computer of power. As a result, I usually just run them until they are obviously not doing a good enough job any more and then replace them.

Most recently, I had an ailing PSU that manifested as the computer spontaneously rebooting; eventually it got so bad that it would reboot *while* booting, and I knew it was time to replace the PSU. I bought a new one off of Newegg and it has been running fine since then. I did have another machine die before that, and it refused to work even after replacing every component; I'm not sure if the PSU was at fault or not, though.

The nice thing about replacing PSUs on the older machines is that it tends to be cheap: they don't require very high wattage, since it's modern GPUs that really suck down the power.

I swear these old PSUs are built heaps better compared to the cheap OEM PSUs you find in budget cases.

The original PSU in my 486 still works but the OEM one in a 1-2 year old case stopped working. I now put in a decent 450W XFX PSU with a 5Y warranty.

They're definitely making them cheaper these days. There's a range of quality to choose from.

What really sucks is that the wattages don't mean much, since sometimes they're referring to peak wattage and sometimes sustainable wattage.

There's always been a range of quality to choose from, and I don't really think the cheap shit PSUs now are any better or worse than the cheap shit PSUs 15-20 years ago. It's just that the cheap shit PSUs from 15-20 years ago have all long since been discarded and forgotten, whereas the more reliable ones have survived.

And about wattages... when they're referring to peak wattage, that'll be a cheap PSU. When they give sustainable wattage, that's more likely to be a decent PSU... assuming it's the actual sustainable wattage. The problem is, about 80-90% of the 'off-brand' PSUs are just plain lying about the wattages... and often any safety ratings as well. Most of the cheap Chinese 450-680W units I've seen are actually ~200W units from one of a handful of low-end OEMs, just with the overcurrent protection removed.

As for the PSUs that come with budget cases, those are the worst of the worst. Never use one of those. I've seen too many of 'em kill hardware, and some even catch fire. (And don't assume your country's safety regulations will prevent the hazardous ones from being imported/sold... there are quite a few ways around those laws, and these companies know all of them.)

Old Thrashbarg wrote:

There's always been a range of quality to choose from, and I don't really think the cheap shit PSUs now are any better or worse than the cheap shit PSUs 15-20 years ago. It's just that the cheap shit PSUs from 15-20 years ago have all long since been discarded and forgotten, whereas the more reliable ones have survived.

And about wattages... when they're referring to peak wattage, that'll be a cheap PSU. When they give sustainable wattage, that's more likely to be a decent PSU... assuming it's the actual sustainable wattage. The problem is, about 80-90% of the 'off-brand' PSUs are just plain lying about the wattages... and often any safety ratings as well. Most of the cheap Chinese 450-680W units I've seen are actually ~200W units from one of a handful of low-end OEMs, just with the overcurrent protection removed.

As for the PSUs that come with budget cases, those are the worst of the worst. Never use one of those. I've seen too many of 'em kill hardware, and some even catch fire. (And don't assume your country's safety regulations will prevent the hazardous ones from being imported/sold... there are quite a few ways around those laws, and these companies know all of them.)

AOpen cases come (or at least used to come) with an FSP PSU. I always considered those to be pretty decent. Been using them for years with no failures or problems.

But generally I tend to avoid the PSU's that came with a case

When problems begin to surface that is when it is best to pull the unit and decide what you are going to do from there. If you pull the unit early on you can easily rebuild it with new caps and sometimes new chokes are needed but usually all you will need is just new caps besides cleaning out any filth. The older units are built better than tanks so failures are rare but they do happen once in a blue moon.

New caps, clean fan, regular cleaning, and it will last long enough to be passed down to your grand kids.

AOpen cases come (or at least used to come) with an FSP PSU. I always considered those to be pretty decent. Been using them for years with no failures or problems.

Yeah, FSP PSUs are generally decent. The PSUs that come from Enlight and In Win are usually OK too... but I don't really put those companies in the same class as the typical 'budget' cases. The ones I was talking about were things more along the lines of Apevia, Powmax (hell, anything ending with 'max' really), Logisys, and all the zillions of unbranded ones out there.