64Mb Simms on a CyberstormPPC ? Also single Simm and 50ns mem..

[Jose]

Hi. I have a 50ns 64Mb Simm lying around. A CyberstormPPC will arrive soon and I'd like to know if I should take the opportunity and buy a similar 64Mb 50ns Simm. Two questions:
- Will the 64Mb Simm be recognized as a 32 Simm? I remember someone posting his 64mb modules were recognized as 16MB :-o
- Since the Cyberstorm only takes advantage of 60ns Ram at the best (if I recall correctly) this 50ns stuff would only be usefull if I decide to overclock it. Any experience on this? Maybe I should just ditch it out and get 4 standard 32MB Simms ? :-?

Thx

[x56h34]

I would get four 32MB simms rated at 60ns in order to create an environment which is as normal as possible for this pricey and easily damageable accelerator card.

[Brian]

I myself use 4*32Mb but iirc you can use 2*64Mb if you put them in 1'st and 3rd simm slot. 50ns will only help if you decide to OC but such delicate and expencive cards as the CSPPC should never be OC'd in my oppinion and still I suggest they get extra cooling.

[Jose]

@Brian
Are you sure one can use 64 Mb and they'd get reconnized, that would be very cool :-)

"delicate.."
Well, the bad problem I've heard about them is heat :-o Come on it's not like the cards are gonna self destruct if one does a little overclocking with the right colling :-D

[Lemonty]

In my CSPPC I have 4*32mb 50ns of which only half is recognized. They were made by Vantis and are EDO. Would the CSPPC manual be wrong in stating that 50ns is supported? I would like to see people saying they successfully installed 128mb 50ns memory in any configuration.

@Brian:

I read in related a posting that overclocked systems needed slower memory (70ns) to compensate in order to work?

[nex4060]

I would not try to overclock it, remember it is old hardware and it gets very hot.
Extra cooling would be a big plus, cool hardware is happy hardware  :-P
I would also get 4*32MB 60ns simms because that is what the card was made for. Some used simms would/should be inexpensive.

remember that some simms are misread, hence the card thinks the simm is only half the size.

[-----------------]
@Brian:

I read in related a posting that overclocked systems needed slower memory (70ns) to compensate in order to work?
[-----------------]

that's wrong. when you incress the timing/clock, the memory timing get's higher and if your memory is not able to keep up, the system will at best be slowed down by the memory. I think that the CSPPC will get unstable.

[Jose]

"Would the CSPPC manual be wrong in stating that 50ns is supported?"

So the manual actually states that?!

"I read in related a posting that overclocked systems needed slower memory (70ns) to compensate in order to work?"

Was that because of the memory notwithstanding the faster busclock, or a problem with the Cyberstorm? If the first one maybe the more rare 50ns Simms would solve the problem?

[Jose]

Forgot to ask, would a single Simm work or does it require two to be present minimum? Like that I could test the one I have, and pray that it would be recognized as two 32 ones on bank 1 and 2 (AFAIK they should be in pairs right?).

[Brian]

@Lemonty

I think you've got it wrong. These figures are taken out of the air since I'm not sure how the formula is in CPU and ram relations so just humor me and I think you'll get the picture.

Lets say you OC your 060/50 with 60ns memory jumpered to 60ns:
10% = 060/55Mhz and 54ns memory (70ns mem=no, 60ns mem=probably, 50ns mem=yes)
20% = 060/60Mhz and 48ns memory (70ns mem=no, 60ns mem=possibly, 50ns mem=yes)
30% = 060/65Mhz and 42ns memory (70ns mem=no, 60ns mem=no, 50ns mem=possibly)

By setting the memory jumpet to 70ns when OC you instead get:
10% = 060/55Mhz and 63ns memory (70ns mem=probably, 60ns mem=yes, 50ns mem=yes)
20% = 060/60Mhz and 55ns memory (70ns mem=no, 60ns mem=probably, 50ns mem=yes)
30% = 060/65Mhz and 48ns memory (70ns mem=no, 60ns mem=possibly, 50ns mem=probably)

So even if you jumper the card to run the memory at slower speed it's running faster then that. So it's always a good thing to have as fast a memory as possible and use the mem jumper if the memory can't take the speed of the OC'ing.

[Brian]

Jose... yah.. there's conflicting information... I've also hear the think of putting them in pairs and that would spoil the chance of using 2 64Mb's... perhaps you can use 4 64Mb or 128Mb ones just for bragging rights? :-D

[Jose]

@Brain
Ok. So if someone is using that configuration (2 64Mb Simms) on a CyberstomrPPC and has a stable system PLEASE let us know :-o  :-)

P.S.
I remember trying a bunch of different Simms (around 10!!) some PC store borrowed to me on a Blizzard 1240 and only about 2 worked!

[Lemonty]

Hmmm I seem to have misinterpreted this posting:
This link

[Effy]

Lemonty : very interesting link though  :-o Seems like you can overclock the MK3 even higher than 75 Mhz  :-o

[Effy]

In a previous post Cass gave a link to the CT60 for the Falcon which is an upgrade board with a 68060 that can be overclocked to 100 Mhz and even has SDram !!!
CPU.............................MIPS..FACTOR   
68060 @ 100 MHz (CT60)..147...25,5    :-o

Can this be done for the Amiga too  :-?  

[Framiga]

IIRC the answer was . . . nope :-( due the low ram bandwidht.

Atari project uses SDram . . .pity.