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Replacement Power Supply in Quadra 605

AEChadwick

Well-known member
the power supply in my souped up Quadra 605 died, and i am too lazy to recap it.

(Q605 is recapped with tantalum, HD replaced with SD card, pretty new VRAM, 128MB RAM, and a full 68040)

Following knowledge from a thread on TinkerDifferent I searched out a MeanWell RPT-60A, a small power supply that provided 12V, 5V, -5V and two GND, a perfect replacement.

I pulled the pin headers off to attach the Quadra Power Connector directly; no actual reason, i just though it looked clean and was quick work.

I printed a small 3D bracket to keep the smaller PSU in place inside the original housing, and restored everything into the case.

It powers up and boots fine. I will do an uptime check later.

(please point out anything i have missed, but it seems to work fine; Just posting here for other folks to reference.)
 

Attachments

  • RPT-60A.jpeg
    RPT-60A.jpeg
    2.6 MB · Views: 191
  • in existing housing.jpeg
    in existing housing.jpeg
    2.6 MB · Views: 195
  • in case.jpeg
    in case.jpeg
    3.5 MB · Views: 203
  • boot.jpeg
    boot.jpeg
    6.1 MB · Views: 203
  • Q605 PSU bracket (stl).zip
    13.1 KB · Views: 12
Excellent timing, I need to rebuild at least one TDK power supply.

Is there anything under the new power supply to protect it from shorting against the metal of the casing? It looks like it's just hanging in space based on the picture.
 

cheesestraws

Well-known member
Is there anything under the new power supply to protect it from shorting against the metal of the casing? It looks like it's just hanging in space based on the picture.

I assume that's what the orange thing in the second picture is? A plastic standoff/bracket to adapt the screw holes and space the PSU away from the metal.

@AEChadwick - could you upload the files for that bracket? I will at some point need to do one or two of these, and having a file for the bracket would make life significantly easier.
 

AEChadwick

Well-known member
Is there anything under the new power supply to protect it from shorting against the metal of the casing? It looks like it's just hanging in space based on the picture.
the existing PSU has a thin plastic membrane underneath the original PCB; the little orange bracket keeps the RPT-60A on the plastic (strangely it was only under that half of the original PCB). In the Tinkerdifferent thread, one guy printed an entire drop-in replacement to hold the new board; i wanted to keep the original metal box, not least of all to re-use the switched power plug.

could you upload the files for that bracket?
the STL is in the first post, it's the zipped file at the end. It's super basic, really just gets the holes in the right places--please remix and share.
 

AEChadwick

Well-known member
Also, where did you source your heatsink w/fan and the replacement fan for your 605?
heat sink fan from amazon, it’s fine. (i printed little "clips" to catch the screws & pressure-fit alongside the processor, but i didn't keep that file...)



for the case i wanted a Noctua, but i could not find anything in 60x60x15... so i got a side-blower. it’s a little noisy, i want something nicer.

 

joshc

Well-known member
heat sink fan from amazon, it’s fine. (i printed little "clips" to catch the screws & pressure-fit alongside the processor, but i didn't keep that file...)



for the case i wanted a Noctua, but i could not find anything in 60x60x15... so i got a side-blower. it’s a little noisy, i want something nicer.

I use a silenx 60mm in mine which fit in place of the original fan.
 

Sinjinhawke

Member
My first post, hopefully I didn't break too many rules.

This was a post I needed to see a year ago when my LC475 power supply died. I am usually pretty lazy as well (and terrible at soldering) but I did order the caps and replaced them all. Fortunately I seemed to have done it correctly as my machine powered back on. Mine is fairly similar to yours but not quite as pimped. I have the full 68040 in but have not swapped the resisters to get it running at 33Mhz (too nervous). Only 36 megs of RAM. Maxed out the video memory. SCSI2SD v6 and ethernet card installed.

Things I don't have are the replacement fan, my stock fan is loud so I like the suggestions here. I also don't have a fan on my processor, do you find this helps prevent lock-ups? I don't leave my LC475 running. Only on when I am playing classic games or feel like browsing MacintoshGarden using Classilla with a WiFi bridge plugged into my ethernet (amuses me being online with this machine).
 

Phipli

Well-known member
My first post, hopefully I didn't break too many rules.

This was a post I needed to see a year ago when my LC475 power supply died. I am usually pretty lazy as well (and terrible at soldering) but I did order the caps and replaced them all. Fortunately I seemed to have done it correctly as my machine powered back on. Mine is fairly similar to yours but not quite as pimped. I have the full 68040 in but have not swapped the resisters to get it running at 33Mhz (too nervous). Only 36 megs of RAM. Maxed out the video memory. SCSI2SD v6 and ethernet card installed.

Things I don't have are the replacement fan, my stock fan is loud so I like the suggestions here. I also don't have a fan on my processor, do you find this helps prevent lock-ups? I don't leave my LC475 running. Only on when I am playing classic games or feel like browsing MacintoshGarden using Classilla with a WiFi bridge plugged into my ethernet (amuses me being online with this machine).
Before you replace the loud fan, just try lifting the sticker in the centre of the fan and putting two or three small drops of sewing machine oil in the bearings, and running the fan upside-down for a couple of minutes in its normal location, then switch it back the right way up. I used a silicone based oil.

Made my fan run way quieter by getting lubrication back in the bearing. No harm in trying before you replace it.

Edit : Oh, also clean the blades if they have grime on them. Dirt/dust unbalances a fan.
 

Sinjinhawke

Member
Interesting. Not sure why doing something like that did not occur to me. Always to eager to replace older components it seems.

Thank you.
 
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