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Amiga computer related discussion => Amiga Hardware Issues and discussion => Topic started by: carvedeye on February 02, 2011, 12:42:36 AM

Title: Location of CIA Chips on a1200 board?
Post by: carvedeye on February 02, 2011, 12:42:36 AM: Hi could some one tell where the CIA chips are located on the a1200 board? they are generating heat and i need to apply some heatsinks to them to disapate the heat.

TIA
Title: Re: Location of CIA Chips on a1200 board?
Post by: mongo on February 02, 2011, 12:54:13 AM: Quote from: carvedeye;611677
Hi could some one tell where the CIA chips are located on the a1200 board? they are generating heat and i need to apply some heatsinks to them to disapate the heat.

TIA

You don't know where they are, but you've determined that they are generating heat?

The CIA chips don't get hot unless there is something very wrong with them. They don't need heat sinks.
Title: Re: Location of CIA Chips on a1200 board?
Post by: carvedeye on February 02, 2011, 11:40:22 PM: Quote from: mongo;611681
You don't know where they are, but you've determined that they are generating heat?

The CIA chips don't get hot unless there is something very wrong with them. They don't need heat sinks.

as i understand CIA chips controll the floppy drive serial etc...my system is playing up floppy disks are not being read and my mouse and gamepad are not responding correctly but when i spray a can of compressed air into the top left corner of the motherboard (a1200 towered) things work for a short time until the cia chips heat up again.
Title: Re: Location of CIA Chips on a1200 board?
Post by: carvedeye on February 03, 2011, 08:15:48 PM: any1?
Title: Re: Location of CIA Chips on a1200 board?
Post by: Franko on February 03, 2011, 08:44:58 PM: I think your a wee bit confused here, the CIA chips in an A1200 are not at the top left of the MB, they are located at the top right and top middle, the chips are marked 391078-01 and on the MB they are marked as U7 & U8... :)

Could you tell us just which chips exactly you are spraying, might help to give a better idea of the problem if you say this seems to cure it... :)
Title: Re: Location of CIA Chips on a1200 board?
Post by: carvedeye on February 03, 2011, 10:07:46 PM: Quote from: Franko;612207
I think your a wee bit confused here, the CIA chips in an A1200 are not at the top left of the MB, they are located at the top right and top middle :)

Is that near the floppy drive connection? if that is where you mean then yes that is where im spraying, when i say top left im saying this becuase my a1200 is in a tower so where as if it where in the desktop case then yes that would be top righ but when it is laid on its side in a tower it becomes the left as it is located in the left corner of the case if you get my meaning. :)
Title: Re: Location of CIA Chips on a1200 board?
Post by: Franko on February 03, 2011, 10:27:38 PM: I've just taken a quick pic of where you can locate the A1200s CIA Chips

(http://i995.photobucket.com/albums/af79/frankosamiga/Amiga%20Pics/CIAsPIC.png)

I've never had any problems myself with the CIA chips but I'll see what I can find out for you as it may be something else that's causing your problems... :)
Title: Re: Location of CIA Chips on a1200 board?
Post by: odin on February 03, 2011, 11:53:59 PM: U8 and U7 if I'm not mistaken.

http://www.amiga-hardware.com/download_photos/a1200mb_rev1d4.jpg
Title: Re: Location of CIA Chips on a1200 board?
Post by: carvedeye on February 04, 2011, 12:08:45 AM: Quote from: Franko;612248
I've just taken a quick pic of where you can locate the A1200s CIA Chips

(http://i995.photobucket.com/albums/af79/frankosamiga/Amiga%20Pics/CIAsPIC.png)

I've never had any problems myself with the CIA chips but I'll see what I can find out for you as it may be something else that's causing your problems... :)

Franko thank you very much that is exactly what i wanted. :)
Title: Re: Location of CIA Chips on a1200 board?
Post by: Franko on February 04, 2011, 12:24:53 AM: Quote from: carvedeye;612288
Franko thank you very much that is exactly what i wanted. :)

I still haven't came up with a solution though... sorry... :(

Never had any problems with the CIAs myself... :)
Title: Re: Location of CIA Chips on a1200 board?
Post by: TCMSLP on February 04, 2011, 09:56:49 AM: I was having major graphical glitches due to temperature - I don't know why some old machines behave in this way (the capacitors on my A1200 all seem to be tantalum not electrolytic - so that rules dry caps out). I fitted (aka bodged) an old PSU fan (blowing air out through the vent) on my untowered A1200 and it's been 100% stable since.

A lot of these old machines seem to display weird heat related issues :(
Title: Re: Location of CIA Chips on a1200 board?
Post by: Franko on February 04, 2011, 11:47:53 AM: @ TCMSLP

In all my years of owning A1200s and running them for on average 16 hours a day 24/7, until I bought one from ebay the other day (problem with gfx flicker, soon fixed) I've never had one break down or show any problems at all... :)

Maybe just lucky, I don't know... but my own personal theory is - I think the less times you switch them of and on the less problems you'll get, sometimes my main towered miggy never gets switched off at all for months on end (my monitors are the same they only go off if there's a power cut)... :)
Title: Re: Location of CIA Chips on a1200 board?
Post by: zipper on February 04, 2011, 03:37:56 PM: Sometimes overheating Lisa causes GFX corruption - especially when covered with a socket to connect a scandoubler.