Upgradeing apollo 1240, what do i need?

[Nikolaj_sofus]

I recently got myself an apollo 1240 accelerator and wonder what i need to upgrade it and where to get it.

The acc. board has the mach 131 chip which i can understand is a must.
I got a mc68060rc50, so thats fine too.
I know that i need a voltage regulator and preferable a socket for the cpu.
Anything else?

Does anyone have any experience desoldering the cpu from the board?

Hope that i can get some input on this

I do have the possibility of borrowing a hot air station at work, but will this actually help me remove the solder?

[rkauer]

You forget the upgraded ROM.

[Nikolaj_sofus]

Originally Posted by rkauer

You forget the upgraded ROM.

Is that somehow obtainable?

[Chain]

sure, EPROM can be burned quite easily,
same for voltage regulator (can make both for ya) and pga socket (ebay)

hardest part is desoldering 040 without any damage

and for hotair station, yup it will help a lot. but practise at some dead pc hardware fist, wit preheater (ie kitchen cooker and IR thermometer) and desoldering pump. And you will need a lot of flux

btw 1240>1260 upgrade topic was discussed many times here, be sure to read it all.

[Nikolaj_sofus]

Originally Posted by Chain

sure, EPROM can be burned quite easily,
same for voltage regulator (can make both for ya) and pga socket (ebay)

hardest part is desoldering 040 without any damage

and for hotair station, yup it will help a lot. but practise at some dead pc hardware fist, wit preheater (ie kitchen cooker and IR thermometer) and desoldering pump. And you will need a lot of flux

btw 1240>1260 upgrade topic was discussed many times here, be sure to read it all.

I will.
Anyway, my reason for the upgrade would be reduced heat rather then increased speed, since im using it in a standard a1200 desktop.

Which actually brings me to another question.
Any ideas about how to get the heatsink off?
It's plastered on there with about ½ a liter of glue!!!

I bought a new heatsink on ebay which is about 3.5 mm lower then the original one so would like to use that until i have the nerve to desolder the cpu.

[Chain]

depends which glues is it, some are dissolvable with chemicals, try IPA, acetone etc

ive also used temperature shock on one heatsing (fridge>hotair gun but thats in your own responsibility

[Nikolaj_sofus]

Originally Posted by Chain

depends which glues is it, some are dissolvable with chemicals, try IPA, acetone etc

ive also used temperature shock on one heatsing (fridge>hotair gun but thats in your own responsibility

acetone doesn't damage the board? thought of actually trying to remove it while the computer were running with the fan off, to see if it would be easier to remove, but i guess it's a bit risky.

[Chain]

it does probably bu you just need to dissolve glue, not whole board. apply it only in dips on glue

[Nikolaj_sofus]

Another question which fit this thread.

When desoldering the cpu. Would it be a good idea to have the heatsink on with the fan running to try and keep the heat away from the cpu itself?

been trying to desolder the socket with the cpu installed on an old 486 laptop and the cpu gets quite hot.

I guess that you also have to take a few pins at the time and then give it time to cool down a bit.

[Chain]

I think it works opposite, if it have heatsink fitted it will be harder to desolder it as heatsing will cool down solder points too

[Nikolaj_sofus]

i know... but my hope would be that it would cool down the core a good deal more then the flimsy little legs.

[Zetr0]

@Nik

if you add a heat sink to the CPU before you do the hot air, but the time you managed to get the pins hot enough to melt the solder, you would of damaged the PCB card and most-likely the CPU itself.

Heat sinks by their very nature draw heat away from the CPU, by adding a sink in this manner you increase the amount of heat you will need to remover the CPU.

In this instance you should not use a heatsink on the CPU.

remember CPU's are made in a furnace as such can take some serious external temperature extremes, this is why you have storing and opperating temperatures.

Damage is mainly caused when CPU's are generating their own heat through electrons pushing transistor gates open and closed that there is a chance of damage.

I am not saying external heat wont kill it... but you could easily take an 060 chip, put it in the over on 280c for 25 minutes no problem. just remember to let it cool gently, dont shock it by throwing it in a bath of cold water....