pekka@burken.bula.se (Pekka Hedqvist) (05/08/90)
I've read in a Swedish BBS that the FastMem memory in the A3000 is
clocked at 16Mhz in the 25MHz A3000 too. If that's right the speed
increase between the 16Mhz & 25Mhz should be quite modest.
Is this correct?
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S W E D E N / "Time flies when you don't know what you're doing."valentin@cbmvax.commodore.com (Valentin Pepelea) (05/08/90)
In article <68@burken.bula.se> Pekka Hedqvist <pekka@burken.bula.se> writes: > > I've read in a Swedish BBS that the FastMem memory in the A3000 is > clocked at 16Mhz in the 25MHz A3000 too. If that's right the speed > increase between the 16Mhz & 25Mhz should be quite modest. > > Is this correct? Currently both the 16 and 25 MHz A3000 are filled with the same ram chips, 100ns I believe. This allows both of them to perform memory accesses within the same amount of cycles. In the future though, the 16 MHz model might have slower ram chips than the 25 MHz, since they don't need to be that fast. There's no such thing as ram chips 'clocked at 16MHz' or 'clocked at 25 MHz'. The useage of appropriately fast ram chips allows the CPU to fetch data without undue "wait states". A wait state is a wasted cycle during which the CPU must wait until the ram chips are ready to return the data needed. Valentin -- The Goddess of democracy? "The tyrants Name: Valentin Pepelea may distroy a statue, but they cannot Phone: (215) 431-9327 kill a god." UseNet: cbmvax!valentin@uunet.uu.net - Ancient Chinese Proverb Claimer: I not Commodore spokesman be
bscott@pikes.Colorado.EDU (Ben Scott) (05/08/90)
In article <11427@cbmvax.commodore.com> valentin@cbmvax (Valentin Pepelea) writes: >There's no such thing as ram chips 'clocked at 16MHz' or 'clocked at 25 MHz'. >The useage of appropriately fast ram chips allows the CPU to fetch data >without undue "wait states". A wait state is a wasted cycle during which the >CPU must wait until the ram chips are ready to return the data needed. Could you post specs on exactly how many wait-states either 3000 is running now (as shipped, standard config)? All I've heard here is "fewer than a NeXT" which is great, but nonspecific... I've heard from a local inside person that it runs a "sustained, effective ZER wait states" (his spelling, not mine!) which sounds great. Also, exactly which increment configurations do the motherboard sockets support? I'm guessing 1 meg increments for the 1megx4 chips and 4 meg increments for the 4megx4? Also, can you combine the two types? How is the config set (jumpers?) or is additional RAM automatically recognized somehow? . <<<<Infinite K>>>> Please note the .sig, this account is expiring soon: -- |Ben Scott, professional goof-off and consultant at The Raster Image, Denver| |Available at FIDO address 1:104/421.2 & the Arvada 68K BBS at (303)424-9831| |THIS ADDRESS WILL BE INVALID AFTER 5-17! Use bscott@nyx.cs.du.edu instead.| |*Real* programmers confuse Christmas and Halloween because DEC 25 = OCT 31!|