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Digby
05-03-2018, 06:37 PM
I like my desktop set up
Its not for gaming. Just a average graphics card
But I now have 4 hard drives and I'd like to get a new Power Supply as my present one is a little noisy.
And I think it works hard especially in the summer
What wattage do you think I would need

dugimodo
05-03-2018, 10:26 PM
Put your specs in here https://outervision.com/power-supply-calculator

It's maybe not perfect, but it's not a bad guide.


my 2c
300W-400W average desktops
450-550W most gaming machines
650W-750W & up high end or multi card gaming rigs or mining rigs

Most people overdo the PSU and that's fine, does not hurt to have a safety margin . I think the quality is more important than an extra 100W of capacity though, a nice 350W gold rated PSU of a decent brand is better than a cheapo 450W - by potentially a huge amount.

Digby
05-03-2018, 10:30 PM
I like my desktop set up
Its not for gaming. Just a average graphics card
But I now have 4 hard drives and I'd like to get a new Power Supply as my present one is a little noisy.
And I think it works hard especially in the summer
What wattage do you think I would need

SurferJoe46
06-03-2018, 06:51 AM
I've always been of the school that more power is better..... but maybe not, as I found out a bunch of years ago.

I had (still have*, really) what you might call a 'marginally capable' PSU once that was getting noisy - but the noise wasn't the PSU trying to make electricity - it was the fan having a hissy fit.

I replaced the fan with a double stack of muffin fans and never had a lick of trouble with that PSU ever again.... and I really pushed it pretty hard with multiple striped HDDs and big SoundBlasters (duals of them) and generally making life miserable for the PSU.

I do not believe that making lower voltages of electricity is a noisy job - look unto the cooling fan, methinks.

* I am very parsimonious concerning spending money to upgrade when what I have works well enough. This is a given more than likely amongst youse prehensilly equipped guys in Upsidedown Land.

piroska
06-03-2018, 08:16 AM
[QUOTE=Digby;1273916 Just a average graphics card
But I now have 4 hard drives and I'd like to get a new Power Supply as my present one is a little noisy.
[/QUOTE]

There are PSU calculators on the net...to be accurate yu could feed in your specifics and see what it says. Then round it up a bit.
500w is probably fine

dugimodo
06-03-2018, 09:36 AM
You should ask someone to merge the threads, I answered the other one.

As surfer Joe mentioned on the other thread, it may just be a noisy fan and you could replace it.

Paul.Cov
06-03-2018, 02:37 PM
I've never had a noisy PSU fan, but I've certainly had a rowdy CPU fan. It was trouble, and at times would fail to spin at all. If it was noisy it was unable to spin at speed, so still wasn't really doing the job.

Check out the fan on your GPU card. It's likely laden with dust and potentially off balance.

dugimodo
06-03-2018, 04:10 PM
You may be right, it might not be the PSU making the noise but I have had a Noisy CPU fan on an otherwise nice silverstone PSU. When I googled it I was not the only one.
I cut a 3 pin to molex fan adapter in half and soldered it onto the old fan cable in the PSU so I could plug a regular case fan in, did the trick.

You need to be careful about bearing types if you want a long term fix though, I think it's the sleeve bearings common in many case fans that don't last well when installed horizontally like in most PSUs.

Digby
07-03-2018, 05:16 AM
Yes talking about noisy fans.
My desktop has always made sort of up and down fan noises.
One minute it is fairly quiet, then there is a sort soft grinding noise, then it goes quiet again.
Its never got any worse over 4 years, so I hvae not worried.
But how to find out which fan it is. CPU, PSU or case?

CliveM
07-03-2018, 07:26 AM
Stop each fan briefly one fan at a time and see if the noise stops.

Lawrence
07-03-2018, 07:39 AM
Guarantee by replacing your CPU/Case Fan with Fans that are manufactured for optimum air movement and quietness you will cut noise by 2/3rd's (done it with mine).Both were a easy swap outs with Noctua Fans

The stock CPU fan on most are noisy out of the box and most rear case fans are just as bad

Also video cards are another source of noise best to choose one that is quite

dugimodo
07-03-2018, 08:25 AM
Yes talking about noisy fans.
My desktop has always made sort of up and down fan noises.
One minute it is fairly quiet, then there is a sort soft grinding noise, then it goes quiet again.
Its never got any worse over 4 years, so I hvae not worried.
But how to find out which fan it is. CPU, PSU or case?

You sure you aren't talking about the noise hard drives make?

Another source of noise is fan grills, if they are poorly shaped they can add a lot of extra noise. Even a normal mesh can be very loud if the fan blades are too close to it. I have run into it a few times, the worst was a side fan on a case window with laser cut slots - sounded like a vacuum cleaner. I've proved this to myself by removing the grill and comparing the noise.

Terry Porritt
07-03-2018, 10:08 AM
You sure you aren't talking about the noise hard drives make?

Another source of noise is fan grills, if they are poorly shaped they can add a lot of extra noise. Even a normal mesh can be very loud if the fan blades are too close to it. I have run into it a few times, the worst was a side fan on a case window with laser cut slots - sounded like a vacuum cleaner. I've proved this to myself by removing the grill and comparing the noise.

Grills are a waste of time, unless there are children around poking things in :) Mostly the holes are too small, and in any case, a wind tunnel test I made up on different grills with various holes showed the flow rate is halved or more. The best I tested had 0.6 the flow of an open window.

There is the reduction in area due to the metal around the holes, and then there there is pressure drop through each hole acting as an orifice. Best to remove and have open for your own computer.

Digby
07-03-2018, 06:27 PM
Sounds like I don't need a case just a piece of MDF and bolt everything to that.!

I get what you mean about the grills though!

SurferJoe46
07-03-2018, 06:32 PM
I've seen some steampunk 'puters on boards, in suitcases and one in a fish tank.

It makes interesting cocktail talk.