I have finally clocked a Cyberstorm MKIII to 80Mhz!!!!

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Hi all,

I have been experimenting for the last year or so with overclocking my Cyberstorm MKIII card. I started by following the information on Daves Amiga Overclocking page. I have bought a few different 68060 cpus in 50 and 60Mhz configs. I have been able to get 66 and 70Mhz speeds with overclocking them and keeping the ram speed to 60ns.

Finally last week I got a hold of a 68060 50mhz cpu with the E41J mask set. I first tested it at 66Mhz, then 70Mhz. I then ran it at 75Mhz without any problems. The highest oscillator I have is 80Mhz, so I tried it and it did not boot. I then took the advice from Daves Amiga Page and made the RAM speed 70ns and it booted fine and works well.
Only problem is, the ram speed at 70ns has dropped compared to the 60ns setting using sysspeed.

I have got a PIII heatsink and fan and the Cyberstorm runs really cool even at 80Mhz. I have decided to stick with the 75Mhz as it runs well at 60ns RAM speed. I must admit though, I really believe I could crack the 100Mhz barrier with this cpu as it runs cooler then room temp. After running it at 80Mhz, I took the fan and heatsink off and touched the CPU and to my suprise, the cpu was cold.

Overall in running power the 75Mhz is great. Quake II with my CybervisionPPC card absolutely flies!!! I will do some more accurate in depth tests in the near future, but I wanted to share my achievement with everyone.

If there is anyone out there with a Cyberstorm MKIII or just experience in overclocking past the 80Mhz barrier, I would be interested in hearing from you.

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I meant to mention this before, I see some people using 50ns simms with their cyberstormppc cards. I have tried 50ns simms with my MKIII Card and I can never seem to get the full amount of RAM to recognise, for example, I have 4x 32Mb 50ns simms and only 64mb fastram shows up in workbench. I use 60ns simms and no problems. Can anyone give some advice here?

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Nope, the SCSI works 100%, I am still getting 34mb/sec xfer rate on the ultrawide bus. I will do up some sysspeed mods and post em here. The MKIII card seems very reliable in overclocking, I am tempted to try 100mhz ;-), but in all honesty the 75Mhz is fine.

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Its the MC version, I got it from an electronics guy in the USA who had one lying around. I paid $100 for it. It was well worth it.

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On the Cyberstorm MKIII card, running at 80Mhz, the card refuses to boot, just basically sits there without guruing. So I dropped the ram to 70ns and it works fine. Seems strange though, one would think that the higher the cpu speed, the fast ram would be required.

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melott wrote:

The question is can a 40mhz WarpEngine be bumped up to
50mhz or more by using a faster ocellerator or faster
68040 and ocellerator?

And if so, will it be stable??

The main thing in overclocking is keeping the CPU cool. The 68040 is well know for running HOT as standard, therefore major overclocking requires major cooling. Most people will agree that a 33% increase is safe, for example a 50Mhz 68060 clocked to 66Mhz, a 40Mhz 68040 to around 54Mhz. I have used a pIII heatsink and cooling fan to keep my 68060 cool. The oscillator governs the speed at which the cpu will run, so if you have a 50mhz 68060, you will also have a 50mhz oscillator. So by taking the 50mhz oscillator out and replacing it with a 60, 66 or 75mhz oscillator you can make the cpu run faster then normal. As I mentioned, the only catch is the extra heat by running the cpu faster then its designed for.

In your case, running the 68040 40mhz at 50Mhz should be reachable, however as with all overclocking you risk damaging your board. If you are to attempt it, get a local electronics store to solder in some sockets for the oscillator, so you can experiment with different speeds. Overall though, I personally love the extra speed and think it was worth my while to take the risk.  

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You can buy oscillators from numerous online stores. Depending what country you live in, but overall the oscillators are cheap to ship because they are only as big as your thumb nail.