MB6582 Fan - Is It Really Needed?

MIDIbox SID
1

I’m approaching the final stages of my MB6582 build and am wondering if the fan is really needed. I absolutely hate fans in gear in my studio and have gone to great expense removing/replacing them in a lot of my gear where possible.

My build currently has 5 x 8580 SIDS with the view of adding a further 3 x 8580 in the future.

I guess I’ll need to install heatsinks on all the SIDS. I’m going to get panels cut and I’m thinking the best option would be to replace the fan cutout on the back panel with some slots to allow cooling via passive convection.

Has anyone got any reason to believe this is a bad idea?

2

This should be perfectly ok. IIRC then the 8580s produce less heat than the old 6581 types. You could always drill some additional holes into the bottom (front area) to allow for convection cooling, if your case doesn’t have any already.

3

I used heatsinks for DIP devices sticked with AKASA thermal biadesive tape and have disconnected the fan

and drilled some additional holes in the bottom of the case

 

P.S.

 

I am not advertising for the brand of the tape…it is only what I used for

feel free to use any other thermal tape you want :smile:

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4

http://discourse.midibox.org/t/topic/16874

5

I think the fan will only add noise. So if you have 8580 or 6582 don’t use one.

6

Running with a disconnected fan here, will try to measure the operating temperature sometime.

7

I could swear that somewhere it was mentioned that the fan was added only for aesthetic purposes (the fan grille looks cool). No guarantees based on following this half-remembered piece of information.

8

I have not experienced electrical or airflow noise whit a “silent fan” ( powered at 5v instead of 12v )

Anyway I have disconnected it

9

not sure how helpful heatsinks will be without airflow.  I have vents on mine and a fan with an off switch, SIDs get crazy hot and some airflow over them wouldnt hurt.  A single SID in a big ass open commodore case with vents is one thing, 8 of those parts (drawing 700 mA +) cramped into a tiny space is a completely different scenario.  

 

Will it work without a fan? Sure 

 

Do you NEED a fan? No

 

Is it good to run everything at an elevated temperature? Probably not and I dont care to find out seeing that there is $250 worth of SID chips in there

10

Altitude, do you use 6581 or 8580/6582?

11

It will also depend on the power option used. Expect less heat in systems using switching 5V regulators. 

12

Altitude, do you use 6581 or 8580/6582?

 

Mine is a 6582 x8 but i’ve built full 6581s, both chips generate a lot of heat

 

It will also depend on the power option used. Expect less heat in systems using switching 5V regulators. 

 

I always use switching vRegs for the 5V rail since I never use the C64 PSU, using a linear one there would compound the problem.