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Amiga computer related discussion => Amiga Hardware Issues and discussion => Topic started by: DiskChris on September 30, 2013, 11:13:28 AM

Title: Underclocking 68030?
Post by: DiskChris on September 30, 2013, 11:13:28 AM
Yesterday I bought a crystal for my gvp 68030 acelerator, but its 16 mhz and the one I had originally was 28 mhz.  Wiki said that the 030 will operate at 16 mhz.  Will this still work or did I leap without looking? :biglaugh:

I wanted to ask this yesterday, but the site seemed down or something...what happened?
Title: Re: Underclocking 68030?
Post by: AmmoJammo on September 30, 2013, 08:36:33 PM
should work...

but, why did you get a 16Mhz crystal if the original one was 28Mhz? :p

most people would have gotten a 36Mhz ;)
Title: Re: Underclocking 68030?
Post by: DiskChris on September 30, 2013, 09:30:08 PM
It was cheap and nearby.  Everything else was in hong kong or something.  Plus I wasn't sure how far above I could go cause cooling in my case isn't real great, and I didn't want to melt anything.
Title: Re: Underclocking 68030?
Post by: Mr_DBUG on October 01, 2013, 12:18:27 AM
I saw the board was down too, odd.
Title: Re: Underclocking 68030?
Post by: Methuselas on October 01, 2013, 01:35:17 AM
Quote from: Mr_DBUG;749142
I saw the board was down too, odd.


Sys Admin probably farted again. It happens a lot, when he eats cheese. :crazy:
Title: Re: Underclocking 68030?
Post by: danbeaver on October 02, 2013, 04:19:38 AM
Back to the question, you can clock it as low as you want and it should work (slowly); over clocking (let's say to 36MHz) may be too fast for the CPU switches or the refresh rate of the ram.  I had an A2630 that choked at 28MHz, and a GVP 3001 that froze above 32MHz.

Look online to the X-bays, Jameco, and DigiKey for a variety of crystals; and remember that the first true digital watch used a tuning-fork -- bloody 1960's!
Title: Re: Underclocking 68030?
Post by: Brian on October 02, 2013, 07:16:50 AM
Quote from: DiskChris;749108
Yesterday I bought a crystal for my gvp 68030 acelerator, but its 16 mhz and the one I had originally was 28 mhz.  Wiki said that the 030 will operate at 16 mhz.  Will this still work or did I leap without looking? :biglaugh:

I wanted to ask this yesterday, but the site seemed down or something...what happened?


If I remember correctly the GVP Impact 2000HC+8 68030 I clocked froze up over 37Mhz. Of cause you can underclock it but if it's just to save money on a crystal its stupid as you drastically cut the potential speed of the board. I'd say get a 33Mhz crystal, it's usually a "safe" option. :D
Title: Re: Underclocking 68030?
Post by: motrucker on October 02, 2013, 05:38:19 PM
Don't use the 16MHz. You will not like the results. GVP '030 accelerators went to 40MHz (mine is 40MHz) or higher.
This is NOT a place to get cheap....
Title: Re: Underclocking 68030?
Post by: LaserBack on October 02, 2013, 10:55:24 PM
underlocking sometimes is useful
I had an apollo 1240 040/40mhz,

in this case this turboboard comes with 80mhz crystal and uses a fan because CPU works so hot and freezes without the fan
once time I was bored and I replaced the 80 mhz crystal by a 50mhz crystal I take from an old PC mobo

the turboboard was rock stable at 25mhz and I had the advantage it didn't require a fan because the 040 was working colder