English Amiga Board


Go Back   English Amiga Board > Support > support.Hardware > Hardware pics

 
 
Thread Tools
Old 24 May 2011, 09:10   #1
alexh
Thalion Webshrine
alexh's Avatar
 
Join Date: Jan 2004
Location: Oxford
Posts: 12,345
A4000 PSU Fan mod

I'm prepping 3 * A4000D units for private sale and part of the prep work is a complete refurb and test of all 3 units.

I fired two of them up last night and OMG the noise from the PSU fans was almost unbearable.

So I opened them up, (whoever designed the release mechanism for the A4000 faceplate needs to be shot!), I whipped out the PSU's (two were the more powerful Liton's and the last a Skynet) and opened them up.

After removing the 2 tonnes of dust and crap inside them, scrubbing the fan blades with an old tooth brush the noise levels were no better

I have to assume that either the original fans were just cheap & nasty and always made this noise, OR they are just past their sell by date.

We had a load of akasa 80mm 12v fans sitting in a box at work which came "free" with heatsinks we buy. (Hopefully they will blow in the right direction because they only have screw holes on one side!)

Problem is that to save money the CBM spec for the PSU has the fan soldered to the PSU motherboard.

10 minutes later the fans are desoldered and the motherboard PSU's are sporting their new fan pin-headers.

A liton and Skynet PSU side by side


Sporting their new Pinheaders


Two fans for the bin and new ones fitted.

Last edited by alexh; 03 January 2013 at 13:02.
alexh is offline  
Old 24 May 2011, 09:34   #2
Hewitson
Registered User
Hewitson's Avatar
 
Join Date: Feb 2007
Location: Melbourne, Australia
Age: 37
Posts: 3,672
Nice job Nothing more annoying than a noisy fan.
Hewitson is offline  
Old 24 May 2011, 10:48   #3
zipper
Registered User
 
Join Date: Mar 2004
Location: finland
Posts: 1,591
Quote:
Originally Posted by alexh View Post
I have to assume that either the original fans were just cheap & nasty and always made this noise, OR they are just past their sell by date.
At least mine was equipped with a sleeve bearing that had developed a vast play into it and was noisy as ....
zipper is offline  
Old 24 May 2011, 11:05   #4
alexh
Thalion Webshrine
alexh's Avatar
 
Join Date: Jan 2004
Location: Oxford
Posts: 12,345
Job isn't done until the PSU's are re-assembled and the A4000's are working once powered back on.

If there is anything I've learned over the years is that big-box Amiga's tend to be critical patients, regardless of their wounds. Open them up and they can easily die on the table.
alexh is offline  
Old 25 May 2011, 04:12   #5
DarrenHD
Registered User
 
Join Date: Aug 2008
Location: London / Canada
Posts: 540
Quote:
Originally Posted by alexh View Post
Job isn't done until the PSU's are re-assembled and the A4000's are working once powered back on.

If there is anything I've learned over the years is that big-box Amiga's tend to be critical patients, regardless of their wounds. Open them up and they can easily die on the table.
I replaced the fans in both of mine too with modern 80mm quiet fans...I also cut out the metal cage to add some windows and improve airflow out the back.

http://www.amiga.org/gallery/index.php?n=2266

My PSU's are the Skynet ones I think, (the one in the right of your photo with the LiteOn and Skynet side by side).

Which one is better?

I'm powering a Cyberstorm PPC, Mediator with a bunch of cards and an IDE cdrom and hard disk...works ok with the Skynet PSU.

Darren
DarrenHD is offline  
Old 25 May 2011, 04:23   #6
Hewitson
Registered User
Hewitson's Avatar
 
Join Date: Feb 2007
Location: Melbourne, Australia
Age: 37
Posts: 3,672
I'd have thought the Lite On would be slightly better quality, at least they're a fairly well known brand.
Hewitson is offline  
Old 25 May 2011, 08:00   #7
rkauer
I hate potatos and shirts
rkauer's Avatar
 
Join Date: Oct 2007
Location: Sao Leopoldo / Brazil
Age: 54
Posts: 3,482
Send a message via MSN to rkauer Send a message via Yahoo to rkauer
@Alexh: those CPU only blows in the screw holes direction (they will blow air into the wrong direction).

You may use they, but bolted to the back of the PSU case or bolted outside the PSU cage.
rkauer is offline  
Old 31 May 2011, 09:25   #8
squidbass
Registered User
squidbass's Avatar
 
Join Date: Sep 2007
Location: Southport The Last Resort
Posts: 193
@alexh

How did your fan mod go? Did you manage to re-assemble the psu?

Squid
squidbass is offline  
Old 31 May 2011, 12:24   #9
alexh
Thalion Webshrine
alexh's Avatar
 
Join Date: Jan 2004
Location: Oxford
Posts: 12,345
Quote:
Originally Posted by squidbass View Post
Did you manage to re-assemble the psu?
Of course. They are very, very easy to take appart and reassemble.

The hardest thing is getting the motherboard connector in and out without damaging the A4000d motherboard. It needs a stoopid amount of force to get it out. If I was doing this again I think I would have looked for an alternative way to test the PSU rather than plugging and unplugging it 10+ times

The next hardest thing is removing the A4000D faceplate, whoever designed that mechanism needs to be shot. If you have a set of angled needle nosed pliers it gets easier but still crazily hard.



rkauer was correct and those fans blew in the wrong direction so I had to buy a different 80mm fan. I went to my local shop and bought the cheapest "silent" 80mm fan which was an Akasa AK-182-L2B (£3)



But the damn thing is as noisy as the original ones!!

So last week I ordered one for £7 online, a Coolink SWiF2-80P. At 7dba (vs 18dba of the Akasa) It has the lowest noise per unit airflow of any 80mm fan I could find. I'll let you know how it works out tomorrow.


Last edited by alexh; 03 January 2013 at 13:00.
alexh is offline  
Old 31 May 2011, 22:14   #10
rkauer
I hate potatos and shirts
rkauer's Avatar
 
Join Date: Oct 2007
Location: Sao Leopoldo / Brazil
Age: 54
Posts: 3,482
Send a message via MSN to rkauer Send a message via Yahoo to rkauer
Alexh, did you see this thread on Amibay?

There are a few options you can do using the original PSU as well.
rkauer is offline  
Old 31 May 2011, 22:55   #11
alexh
Thalion Webshrine
alexh's Avatar
 
Join Date: Jan 2004
Location: Oxford
Posts: 12,345
Erm, thanks. The original A4000 PSU is more than I could ever need.

All I wanted was to "silence" the fan noise from the old, cheap worn out dust encrusted monsters.

Modding for modding sake is not my thing.

With hindsight I would have quadrouple checked the airflow values. The new SWiF2 fan is completely silent at the fastest (1100 RPM) setting but the airflow feels like a fraction of the original one.

Last edited by alexh; 31 May 2011 at 23:09.
alexh is offline  
Old 31 May 2011, 23:45   #12
Loedown
Precious & fragile things

 
Join Date: Feb 2009
Location: Victoria, Australia
Posts: 1,946
With most PSU modern or antique, they seem to need a fan only in extreme cases. For the most part I have seen some computers that ran quite happily for many years with a dead fan in the PSU. I don't recommend this only state a fact.
Loedown is offline  
Old 31 May 2011, 23:50   #13
alexh
Thalion Webshrine
alexh's Avatar
 
Join Date: Jan 2004
Location: Oxford
Posts: 12,345
Yeah, I don't think the PSU electronics needs the airflow but with this being an A4000d-CR it has both a 68030 and 68060 powered at the same time. (Pretty sure the design does not remove power to the onboard CPU when there is a SLOT CPU fitted?)

I'll put it back together and put a thermal probe in there and run it for a bit.
alexh is offline  
Old 01 June 2011, 03:28   #14
8bitbubsy
Registered User

8bitbubsy's Avatar
 
Join Date: Sep 2009
Location: Norway
Posts: 1,355
The problem is that the fan header in the PSU is delivering 12v, and this is interpret as "max" to the fan. Try cut the 12v trace and find a 5v and jumper it to the pin, or get a resistor to limit the current a bit. I did this mod to my Amiga 2000 PSU, and the only solution was the resistor (12v = super noisy, 5v = almost no spin at all, resistor = perfect).
Even cooler would be to find a trimmer resistor (pot) and drill a hole for it in the PSU case -- which results in super cool user-adjustable fan speed!
8bitbubsy is offline  
Old 01 June 2011, 09:04   #15
alexh
Thalion Webshrine
alexh's Avatar
 
Join Date: Jan 2004
Location: Oxford
Posts: 12,345
The new fans are silent at 12v and they have a PWM controller with 3 settings built in.
alexh is offline  
Old 01 January 2013, 14:31   #16
hooverphonique
ex. demoscener "Bigmama"

 
Join Date: Jun 2012
Location: Fyn / Denmark
Posts: 1,093
Quote:
Originally Posted by Hewitson View Post
I'd have thought the Lite On would be slightly better quality, at least they're a fairly well known brand.
The A4000 PSU is *not* by the LiteOn brand.. It's called 'TAIWAN LITON'
hooverphonique is offline  
 


Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools

Similar Threads
Thread Thread Starter Forum Replies Last Post
A4000 PSU -> Mini-ATX PSU mod keropi Hardware mods 53 09 December 2019 03:52
A4000D PSU Fan with Temperature Sensor control. slaapliedje Hardware mods 3 06 June 2013 18:38
Amiga 4000 PSU Fan Mod edd_jedi Hardware mods 8 30 December 2012 17:02
Papst 8212JN PSU fan for Amiga 1000 Paul_s MarketPlace 0 18 May 2010 11:16
Amiga 4000 PSU Fan hese support.Hardware 6 22 September 2008 01:02

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT +2. The time now is 19:04.


Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2020, vBulletin Solutions Inc.
Page generated in 0.08944 seconds with 13 queries