68kMLA Classic Interface

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​LC 575 logic board in a Color Classic: ​Mods to the board?
Posted by: BadGoldEagle on 2017-09-11 11:44:19
Great to hear you've finally got it working! No idea why it didn't work with 7.6 though. But can you get back to 8.1 after that, right?

You've got a pretty maxed out machine now! What's next?

Posted by: mraroid on 2017-09-11 12:53:41
Yep, I can move from 7.6 to 8.1 and back again. 

Next project is to put a heat sync and fan on my 68040 CPU.  I hope to overclock it from 33Mhz to 40Mhz.  I don't know if it needs a heat sync and fan, but I have one that will fit the CPU and I know it will not hurt anything.  Because I am running SCSI2CF card rather then a mechanical SCSI hard drive, I think I am drawing less current from the power supply.  So I am going to grab 12V from the hard drive power connector.  I think I will be OK.....

mraroid

Posted by: register on 2017-09-11 14:46:30
If someone likes to juggle different boot volumes by swapping flash memory cards (as mentioned above), consider to use just one card with an appropriate set of different partitions. It is possible to put a set of several boot volumes onto just one drive. You can either select the volume to boot from with the appropriate control panel, or else select by addressing the desired volume at boot time with a »magic« key combination (at least with HDT formatted SCSI disks).

Posted by: olwilli on 2017-09-11 15:39:37
mraroid -  you really should use a heat sync with a fan... if you put it to 40MHz it gets very warm 😉

In my CC I changed the fan in the case too - on the one hand its much more quiet, on the other hand it cools the components better.

You got already the components? For the CPU the most people use cooling units from a 486 CPU.

Posted by: mraroid on 2017-09-12 11:05:47
I was going to change the main fan in my Color Classic  But I could necer find any good data for the original fan.  Do you have a link or some additional info on your main fan mod?  I would like to increase the air flow.

Thanks! Here are photos of my heat sync and fan.

mraroid

hs1.jpg

hs2.jpg

Posted by: olwilli on 2017-09-12 12:19:51
I use this here:

http://cdn-reichelt.de/documents/datenblatt/C800/HA80251V4.pdf

It fits perfectly and got and 3 times bigger airflow than the original one. That thing costs in Germany only 2,25€.

Posted by: mraroid on 2017-09-13 08:55:01
olwilli....

How did you provide the 12V for that fan?  Did you pull it off the hard drive power supply?

That fan looks prefect.  I would like more air flow inside my Color Classic.

mraroid

Posted by: mraroid on 2017-09-13 09:59:57
Here are a couple of photos of my 68040 heat sync and fan.  I had to grind the lip off each end of my gold color heat sync.  But now it fits well and coves the 68040.  You can see white on the gold heat sync where I grinded it a bit.  I am extending some wire and about to put a thin layer of thermal paste on between the CPU and heat sync.  The heat sync has 4 black plastic hooks that keep the heat sync good and tight. 
 
I am very happy with the fit.
 
mraroid

rsz_hs1.jpg

rsz_1hs2.jpg

Posted by: olwilli on 2017-09-13 23:58:15
mraroid - yes, the power for the fan comes from the HDD Power Cable. Its connected with an Y-Cable.

Posted by: mraroid on 2017-09-14 13:17:56
olwilli.....

I am unable to bring things into Ecuador inexpensively.  But I did find a fan in my own personal stock of computer stuff.  It was a perfect fit for a replacement fan in the Color Classic.  I will enclose a data sheet.  It is a Panaflo model # FBAO08A 12U. 12 is for 12V and the "U" is for "Ultra High Speed".
 
Just using my hand over the outside of Color Classic, I can tell I have more air flow.  How much more, I do not know.  But it is better.
 
This fan has a slight annoying sound to it.  The volume is low, but the original Color Classic fan was whisper quiet.  I hope I can forget the sound...  🙂
 
I tried to contact the web master of the new PowerCC.org.  But the "send email" part of the web site is not working.  I think this person could archive the data sheet you posted and perhaps this one, so folks that want to upgrade the fan in a color classic would know what type kind and size to look for.  
 
Thanks for all your help.
 
mraroid
 
 
rsz_ccfan.jpg

CCFan2.pdf

Posted by: mraroid on 2017-09-14 13:19:12
here is the fan in the CC case....

mraroid

rsz_ccfan2.jpg

Posted by: 68krazy on 2017-09-14 18:20:41
Looking good! I think fan swaps in this machine are a very pleasing mod. Also easy—any fan will do as long as the CFM is sufficient and the noise level/type of noise is agreeable to you. When I restored my LC 550 (extremely similar to the CC, link to the thread is in my signature) I used a Noctua fan. CFM went up and the drone of the original fan became a much more pleasant "whoosh" sound. I'm a happy camper.

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