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Amiga computer related discussion => Amiga Hardware Issues and discussion => Topic started by: Chain on July 10, 2005, 09:23:32 PM

Title: CBM A3640 overclocking or 040/40 replacement - its possible?
Post by: Chain on July 10, 2005, 09:23:32 PM

Im wondering if is possible to change cpu atleast 33 or 40mhz (oscillator too).
Any help, experience etc. are welcome.

 - 8-) - = = = THANKS A LOT = = = - 8-) -  

Title: Re: CBM A3640 overclocking or 040/40 replacement - its possible?
Post by: Lemmink on July 10, 2005, 11:25:58 PM

28 MHz should be possible, 33 MHz are critical. It`s not the processor that makes problems it`s all the other parts that are on the board.
Anyway even if you could successfully clock an A3640 at 40 MHz it would still be outrun even by an Apollo4040 @ 25MHz.
You can`t win much with rising the clockspeed on an A3640 as the design (especially the lack of own RAM) sucks-

Title: Re: CBM A3640 overclocking or 040/40 replacement - its possible?
Post by: Chain on July 11, 2005, 08:21:34 AM

so i will try to replace only oscillator for a few mhz highher version, np .)

Title: Re: CBM A3640 overclocking or 040/40 replacement - its possible?
Post by: Crusher on July 11, 2005, 08:43:38 AM

You should put an extra fan that blows the air on upside and downside of the card. My A3640 became very hot. :-)

Title: Re: CBM A3640 overclocking or 040/40 replacement - its possible?
Post by: Crisisdog on July 11, 2005, 01:41:43 PM

I've tried to overclock two A3640 boards to 33MHz but was unsuccessful.

Don't quote me on this, but I think one of the limiting factors here is that the A3640 clock also takes control of some of the motherboard timing circuits.  Thus, when you overclock the card, you also are overclocking the motherboard.  Other accelerator cards besides the A3640 seem to leave the motherboard clock alone.  At least this is the impression I get by the jumper configurations that need to be set on my A3000 motherboard when switching between an A3640 and a WarpEngine 4040.

You're best bet is to just look for another accelerator board if you need higher speeds.

Title: Re: CBM A3640 overclocking or 040/40 replacement - its possible?
Post by: alexh on July 11, 2005, 02:08:05 PM

To overclock the A3640 correctly for higher speeds you need to alter a delay line on the board. There was daves website that showed you (starnet.au?) but it's now gone :(

Title: Re: CBM A3640 overclocking or 040/40 replacement - its possible?
Post by: Chain on July 11, 2005, 03:28:20 PM

A3640 just arrived, but no works. Dude who sell it says it was wirking in his A3000. any jumpers on motherboard must be switched?

CD-ROM(SCSI) LED is still lit and it wont boot

Title: Re: CBM A3640 overclocking or 040/40 replacement - its possible?
Post by: Cyberus on July 11, 2005, 03:33:52 PM

rotking?
:-?
The Evil Dead?


Keep an eye for other 3rd party CPU cards, like WarpEngine, Cyberstorm, etc if I were you, because you can add fast(er) on-card RAM for a start...

Title: Re: CBM A3640 overclocking or 040/40 replacement - its possible?
Post by: Crusher on July 11, 2005, 03:35:02 PM

Info on A3640 (http://homepages.ihug.co.nz/~miles.j/a3640.html) :-)

Title: Re: CBM A3640 overclocking or 040/40 replacement - its possible?
Post by: Chain on July 11, 2005, 04:21:08 PM

Cyberus: i gave evil $20 for it, u know...

Title: Re: CBM A3640 overclocking or 040/40 replacement - its possible?
Post by: Chain on July 11, 2005, 04:22:59 PM

oh man, this :-D is :-D  it :-D

thanks a lot!


jumpers jumpers ... hmmmm bumpers funkers... tooo hot today or im just dumb :)


my A3000T:
mobo 6.1
ramsey -04
buster -07
dmac -02 ( scsi will be problem i think :)

Title: Re: CBM A3640 overclocking or 040/40 replacement - its possible?
Post by: Chain on July 11, 2005, 04:54:59 PM

8-) TADAAAA  :-D  :-D  :-D  

(http://chain.3dgrafika.cz/temp/miggy/A3640_onboard.JPG)

(http://chain.3dgrafika.cz/temp/miggy/A3640_sysinfo.JPG)

and SCSI still works fine

(http://chain.3dgrafika.cz/temp/miggy/A3640_scsi.JPG)

Title: Re: CBM A3640 overclocking or 040/40 replacement - its possible?
Post by: x56h34 on July 11, 2005, 05:00:42 PM

Running an A3640 without a heatsink...not a good idea.

Title: Re: CBM A3640 overclocking or 040/40 replacement - its possible?
Post by: Chain on July 11, 2005, 05:12:03 PM

i know :) this is only for photo, i just wanna see 040 numbers :)

Title: Re: CBM A3640 overclocking or 040/40 replacement - its possible?
Post by: jlariv8957 on July 11, 2005, 06:14:46 PM

Hi,

Check this link it's exaclty what you need !

http://members.iinet.net.au/~davem2/overclock/a3640.html

Title: Re: CBM A3640 overclocking or 040/40 replacement - its possible?
Post by: jlariv8957 on July 11, 2005, 06:16:07 PM

you can find the dave's website at

http://members.iinet.net.au/~davem2/amiga.html

Title: Re: CBM A3640 overclocking or 040/40 replacement - its possible?
Post by: Chain on July 11, 2005, 06:17:35 PM

YOOO!  holy grail :)))

THANKS!

There is your reward :)

(http://chain.3dgrafika.cz/temp/miggy/A3640_fan1.JPG)

(http://chain.3dgrafika.cz/temp/miggy/A3640_fan2.JPG)


 :-D  one more thanks for help!

Title: Re: CBM A3640 overclocking or 040/40 replacement - its possible?
Post by: Crusher on July 11, 2005, 07:03:37 PM

Ehm.. those clips that you use to hook the heatsink, are they unprotected metal? If so, then remember that there are unprotected cpu-pins under there too. :-)

Title: Re: CBM A3640 overclocking or 040/40 replacement - its possible?
Post by: Chain on July 12, 2005, 05:27:34 AM

its original clip for 040, it prefectly fits. theres only a very small hooks. i was checked it :)