A1200 Fan and heatsink placement probs

[Amiga1992]

Hey guys,

I've got this small fan and heatsink sitting here for a while. The reason why I acquired it in first instance was to put it inside my A1200 to let it be cooler. Tried to fit it once but realized that it wouldn't.

Now I'm a tard for letting it rot there without trying one more obvious thing: sepparate the bloody fan and heatsink!

Anyway, I don't know what's right to do. I want to put this atop my 3.5" superslim drive because the bugger does run hot and I fear for my miggy's sanity. I got sick of having to put a noisy camping fan behind the miggy everytime I operate it in extreme heat situations (ie a gig in a club, full of sweaty dancey bastards). I don't know if it is right putting just the fan, or would the fan be useless without the heatsink?

What I thought of was what you see in the next 3 pictures:



Would this work or is it dumb? Is the fan useless if not atop the heatsink? will the fan drain too much power from my PSU? (I'm using the sturdier A500 brick but I might as well use the nominal A1200 brick). It takes 0.06A.

For all it's worth, here's my config:
*A1200 (rev 1D.1)
*Microbotics XA1230 030@50 with 32MB in it
*Seagate superslim 3.5" 1Gig drive, mounted in there by miracle, I hope it never moves or I'll fry the mobo :P I set it atop some rubber thingies like those you find below the miggy. Seems safe and it fits snuggly, bt still, I;'d like to replace it by a 2.5" one day.

Thanks in advance!

[edit] Forgot to ask, how do I secure the shit in place? Do I glue it with a silicon pistol or something?

[adolescent]

Honestly, a fan like that isn't going to do much good on it's own. I'd get a 60mm slim line case fan instead. Probably move more air and be a bit more quiet.

And, to think you gave me a hard time about double taping my HD into my A1200. Shame.

[Amiga1992]

Originally posted by adolescent
And, to think you gave me a hard time about double taping my HD into my A1200. Shame.

Hey, ou should have seen how the original owner had this set up. It was a downright mess! I have improved it tenfold by tidying up the cables and using the rubber cushion thingies to hold the HD instead of a lame, heat-prone antistatic bag!

What's teh problem with this fan you say? And would the slimline one fit? This one touches the uipper case therefore it would not spin.

would my proposed setup do pish all? And a questionm remains: How do you stick this shit into place?

Cheers for yer answer

[Enverex]

Actually it wont have any affect at all. Firstly because the club is hot, you will just be moving hot air and replacing it with other hot air, and secondly, sticking a fan on the HD wont do anything as the air will just blow a small amount around the case, again, just stagnant air. If you attach the fan to the drive like in that picture then it cant do anything anyway as it cant blow the air through as there is no space to blow it onto, which is why it needs to be on the heatsink.

[Amiga1992]

Hmm.. the A1200's vents are just above the location of the fan. I didn't understand why this thing has to be atop the heatsink.

Where should I put the bloody thing so it eases up the heat produced by the HD, then?

[Enverex]

You need it so it blows air from outside, directly down onto the drive. You cant stick the fan directly on the drive as then there is no where for the air to go through the fan, it just blows back on itself, giving no productivty and high noise output (which is why you can only place them on grills or heatsinks, so that there is somewhere for the air to actually go the other side).

[Syko]

another possibility is to put the fan 'upside down' against the vents of the a1200, so it blows air out of the case, rather than moving warm air inside it.

Carefull sitting of the fan should allow you to get reasonable air flow over the HD, thus cooling it down.

But you'd still be better off with a 60mm slimline case fan doing the same job....

[Unknown_K]

Laying a fan against a flat object will not move any air at all (they blades suck air from behind them and push it out the front and if there is no air to push because the path is blocked they do nothing).

Best thing to do it screw the fan to the inside of the grills on the top of the A1200 to suck the hot air outside of the case.

Unless a specific component generates alot of heat (processor's mostly) dont use a heatsink at all. Heatsinks just transfer heat from a hotter object to a cooler one. Putting a heatsink on top of a cool running 2.5" HD will just make the HD run warmer if the air in the case is warmer then the drive.

My 030/50 in the a1200 runs kinda warm because the designers put a heat producing chip upside down in an area with no airflow. Removing the trapdoor will probably do much more to keep your system cool then putting a fan in an area that doesnt get that hot to begin with.

[Amiga1992]

Originally posted by Syko
another possibility is to put the fan 'upside down' against the vents of the a1200, so it blows air out of the case, rather than moving warm air inside it.

Errr.. call me an idiot, but the way I put it I thought it would take the air from below and blow it OUTSIDE the case through the vents. That's why I located it there, not to suck in the heat and throw it back at the HD! I have to flip it and stick it to the 1200's plastic case?

Unk, the drive is a 3.5" once, and that zone gets mighty hot, specially since the processor and custom chipsetry lies just behind the HD. Opening the trapdoor will cool up the accelerator only, which is cool already and needs no extra air flow. That's why I want to put a fan in hear to ease up the heat generated by teh HD and therefore easing up the heat produced underneath it by the HD+custom chipset. maybe I should put the heatsink below the HD, over the large VLSI chip? (Gary?)

[Unknown_K]

Originally posted by Akira
Errr.. call me an idiot, but the way I put it I thought it would take the air from below and blow it OUTSIDE the case through the vents. That's why I located it there, not to suck in the heat and throw it back at the HD! I have to flip it and stick it to the 1200's plastic case?

Unk, the drive is a 3.5" once, and that zone gets mighty hot, specially since the processor and custom chipsetry lies just behind the HD. Opening the trapdoor will cool up the accelerator only, which is cool already and needs no extra air flow. That's why I want to put a fan in hear to ease up the heat generated by teh HD and therefore easing up the heat produced underneath it by the HD+custom chipset. maybe I should put the heatsink below the HD, over the large VLSI chip? (Gary?)

I am using a 2.5" IBM laptop drive (3.2 or 3.8gb cant remember) and it doesnt get hot.

Build an L bracket and mount the fan so it blows across the HD, assuming there is enough clearence.

[Amiga1992]

Originally posted by Unknown_K
I am using a 2.5" IBM laptop drive (3.2 or 3.8gb cant remember) and it doesnt get hot.

I'll repeat myself again. My drive is 3.5"! That's why I want to put this bloody fan. a 2.5HD drive runs much cooler than a 3.5" one.

There's no clearance to put the fan atop the heatsink, even less to L-mount it.

I think I'll let it be. And get a 2.5HD someday.

[Enverex]

I really doubt you need to care about the heat. I have drives stacked in my tower that get VERY hot, and I never have problems with them.

[woody57]

I have a solid background in solving engineering problems this is a question of convection & conduction

Syko is on the right track the below pathetic top picture shows the simple kitchen fan use where steam is extracted and cooled by the outside air

However in the confined space of your desktop miggy you never want things to get that HOT

{ steam out of your ears at my dumb rambling YES }

The bottom picture shows a simplified classic solution where cooler outside air is DRAWN in through a port or vent is drawn across the heat source and this warmer air then EXPELLED.

This being a classic heat exchange


Now the problems in the 1200,s scenario

The fan as Syko said would have to be mounted to extract air to the outside upside down under the top case vents

This requires a filtered port or grill to be created & mounted in the bottom or back of the case in order that outside COOLER air can be drawn in.

The inards of a desktop 1200 are cramped as it is and with the exception of one blanking plate in the 1200's back there are NO OBVIOUS SITES TO USE

Also now you are into the vacum problem when you draw in air , you also pull in dust & dirt so the mesh needs not to be so small as it allows insuficient cool air in to EVEN COOL the fans motor :eek

Or you have so many EXTRA holes your beloved Miggy resembles a drive by victim

So a cleanable or replaceable filter is recomended


Finally the brushless fan 5volt pictured has a very low current demand so it should not tax the power supply providing IT DOESN'T overheat due to insuficient air being drawn in


If nothing else I hope my crummy diagrams & nasty labeling give you a laugh

And No gentlemen this does not mean the old git is going to remain sensibe again

[Amiga1992]

That's exactly teh kind of explanation I was looking for, now I know why this wouldn't work out.

Originally posted by Enverex
I really doubt you need to care about the heat. I have drives stacked in my tower that get VERY hot, and I never have problems with them.

Nothing to do with my situation, my PC is out of risk as well no matter how hot teh HD gets. I'm not fearing about the HD, I'm fearing about teh components. The space betwee nthe HD and the motherboard is smaller or not greater than one centimeter, and it's placed at the part of teh mobo that gets hotter. Obviously this doesn't happen in my A1200...

Is it that no one ever mounted a 3.5" inside an A1200 desktop case and you don't understand what I'm going on about? It gets mighty hot in there for sure. Adolescent surely knows.

[woody57]

yes thats it run


the fogeys back rambling again

I often had to deal deal with delicate equipment over heating and either shutting down till it cooled or adding EXTRA convection.


Unlike modern aplifiers with hi -tech designed alloy heat sinks and custom fans the old valve amps { yes I am ancient}

Were prone to frying the early tape loop based wem copycat or melos echo machines because as every basic science student knows HEAT Rises

The old tape echo machines were allways on top of the stack to allow for easy change of patch cables & remote foot switches .


What has this to do with Akira's Question ?

Because it is clear to see from the photo,s that the slimline drive has had to fitted into the space the designers left for normal cooling convection of those CHIPS under where the drive now sits .

Hence the case vents in the top to allow this warm air to escape, as the original 2.5 drive would be cradle mounted under the keyboard .

The larger 3.5 is acting as ROAD BLOCK on the designers convection path so it is right that he is concerned as to the implications to the components beneath the drive .

While the idea of thermal shunts is nothing new { as in an car engines water cooling system & fan }

The aplication of an assisted system is a requirement in these situations




I've not gone mad & I certainly WOULDENT OUTLINE HOMEMADE WATER COOOLING INSIDE A COMPUTOR


But we need a heat exchange system that gets round the stolen space problem without the classic 1200 looking like a Heath Robinson contraption.


An externaly placed fan will only blow over the outside case & remove a small percentage of extra internal heat build up.

Because internally the bottom of the drive acts like an oven wall that might get warm>hot but NOT to the increased internal temp as more heat energy is being created from underneath !

In effect the drive acts as insulation


So we needs to create a FLOW from underneath it

Air cooling alone in confined spaces is problematic because of the dirt question raised earlier { dust & dirt build will also act as insulator to cause component failure acting like a jacket to hold in more heat }


Because of the limited available space & the fact you arn't expected to have a custom refridgeration construction workshop in your home

The solution involves adding a series of conduction paste conected addtional heat sinks across the top of the hot IC's { In my day no paste but touching the valves glass }

Because alloys are great at exchanging heat more efficiently than air alone you link them to a single LARGER EXTERNAL VANED HEAT SINK across which you can blow fan assisted air .

Back in the 60's we used alloy tubing that could be bolted in place as it having a central bore to assist the setting up of the conduction convection path .


Think car brake pipe ! its cheap its easy to form into coils or bends and it doesn't have to be big to do its job

Because its only acting as a carrier to the larger external mounted cooler.

At least that way it could be mounted on the left side of the case without interfereing with the floppy or rear ports



We didn,t have brushless fans and instead had to rely on the old mains voltage convector fan motors with air scoops
Big ugly but cheaper than replacing expensive effects in the middle of a set with the audience & the band wanting your BLOOD !

[Amiga1992]

That's a fucking mod and a half, but probably more worth of my time than the previous attempt ;D

Got to add that an external fan DOES help keeping the machine way cooler, mind you is a powerful one. It makes lots of air flow through the vents and below the machine where it's getting hotter. It's a solution but a messy, noisy one at that, and I rather have it all self-contained.

I fon't know much about this heatsink shit but if you help me along the way I might be able to perform this supermod ;D Thanks for your input, ye ole fogey

[Bloodwych]

Hey! I’m back, well for a week anyway. Looks like nobody missed me!

Hmmmm. I know you bought that A1200 second hand and I’m not sure if you’re aware it’s missing the top metal shield that normally covers the motherboard. Do you still have it?

The reason I ask is in the past I managed to get normal height A1200 3.5” drives to fit in the top left hand corner after cutting away a small portion of the shield that lies just above the power socket. It’s the only part of the shield assembly that sticks up and once it’s cut away 3.5” drives fit fine. I then neatly covered the top left section of the metal shield in black electricians tape, and placed the drive on-top.

Recently, I took a slimline Seagate out of an old PC (same as yours? are you sure that’s slimline? looks a little fat in the photos) and it went in the case easily in that top left hand corner. Again, like before, (since it sits on-top of the metal shield) there is no problem with ventilation. In fact, it was too slim and I had to use a small piece of sponge between the case and drive to wedge it in that top left corner.

Without the top metal shield, can’t really make any other suggestions apart from grab a 2.5” drive, so little room in the A1200. If only we had a cable for that micro drive in the other thread. Then you could just blue tack the thumb-sized 3GB drive in there!

[Amiga1992]

The guy said it's ultraslim. It's slimmer than my otehr hard drives fer sure, about half of them. In any case, I know the metal thing is missing, I can't nab it. He surely threw it away. Mind you not all models came with the metal plate. I've seen A600s with metal plates, while my A600 never came with any. Probably this is a UK thing, my A1200 model is US, and my A600 model was German.

[woody57]

Rather than just spout Akira I will get back on this issue backed up with some digital photo,s of how to.


Using a minimum of tools & lowest expense .

Whats the good of theorey without its application ?


The good news is the 1200 does have the space on its left for a vaned plate to be mounted & I.ll use my spare A600 for the scale photo fits

{ yes I know its a different case BUT the left side was recomended for early ATAPI extensions for adding external cheap cd rom addaptions before hard drives got faster & bigger storage wise rather than physically}

Heck I can leave it on the other site & link it or let Paul aga have it for his how too,s on his site .



It gives me something practical to do instead of winding up EAB members with my scribbles


And if its badly editted , poorly laid out & has BAD GRAMMER you,ll all know its a woody original

[Bloodwych]

Probably is slim Akira, just the clearance seems very small with the top metal shield removed.

Woody seems the best bet at the mo. I said this in the "Roll call" thread but I'll repeat it here - I like your comic strip art woody! And now it seems it might be put to some practical use!