What is the maximum memory that can be used under os 4.0 classic ?

[nikodr]

Ok i was searching on the internet to find info why the old kv8 max 3 motherboard that has an athlon64 3200+ can handle only 2gigabytes (or 3) of ram while having access to a 64bit processor.Answer was because of the memory controller on the motherboard.

Now on the amiga i never quite understood the way memory works.There are some solutions that memory could go up to 1 giga of ram or more,and that is for 68k based s accelerators on a4000.Is it a problem of the cyberstorm ppc memory controller ?Maybe a new patch of the mach chips it has could fix it ?

I am saying this because i saw upgrades that could bring a cyberstorm up to 400mhz.In everyday computing life on internet we need more than 256 of ram unfortunately.
So has anyone ever tried to do it?

[Pyromania]

1 Yottabyte of RAM is the max for 4.0 Classic.

[Zac67]

Ok i was searching on the internet to find info why the old kv8 max 3 motherboard that has an athlon64 3200+ can handle only 2gigabytes (or 3) of ram while having access to a 64bit processor.Answer was because of the memory controller on the motherboard.

Not really correct. The RAM controller of an Athlon64 system is integrated in the CPU.
But depending of maximum number of DIMMs / ranks and maximum supported chip density, there's a physical maximum (e.g. 3 GB for socket 754) - you don't expect an Athlon64 mobo to support 18 Exabyte, do you?

Now on the amiga i never quite understood the way memory works.There are some solutions that memory could go up to 1 giga of ram or more,and that is for 68k based s accelerators on a4000.Is it a problem of the cyberstorm ppc memory controller ?Maybe a new patch of the mach chips it has could fix it ?

Theoretically possible but will not happen.
The hardware architecture could support up to 4 GB of RAM (or even more with virtual memory), but at least OS 3.x limits this to 2 GB.

[Karlos]

I am saying this because i saw upgrades that could bring a cyberstorm up to 400mhz.In everyday computing life on internet we need more than 256 of ram unfortunately.
So has anyone ever tried to do it?

Theoretically, no existing version of AmigaOS can use more than 4GB of address space, since all pointers are 32-bits wide. Not all of that address space can be RAM either, as you have to map hardware into it too. IIRC, ~2GB is the limit for RAM.

However, for any version running on a classic machine, you'll run into other hardware limits before that. For instance, 256MB of Fast RAM is the physical limit for BlizzardPPC boards, since each slot only recognises SIMMS up to 128MB.

On the CyberstormPPC, I think the limit is 128MB. You can, however, add Z3 RAM, so shove a couple of ZorRAM sticks in the machine and you could probably boost over 1GB. However, that increase would come at a cost in performance, since the CSPPC would be forced to access it via the Zorro bus, which is much slower than it's own local memory bus.

I can confirm, however, that OS4 classic is perfectly usable on my 256MB BlizzardPPC.

[ajk]

AmigaKit demonstrated 1.2GB of RAM in an A4000 somewhere, so at least that can be done; though such a feat has little practical use Don't recall whether that system had OS4.0 or 3.x.

[Crumb]

On the CyberstormPPC, I think the limit is 128MB. You can, however, add Z3 RAM, so shove a couple of ZorRAM sticks in the machine and you could probably boost over 1GB. However, that increase would come at a cost in performance, since the CSPPC would be forced to access it via the Zorro bus, which is much slower than it's own local memory bus.

OS4 for CSPPC just accepts CSPPC local memory. Motherboad&Zorro memory modules are completely ignored. Joerg Strohmayer decided that Motherboad&Zorro memory support should be dumped in favour of swap memory (even thought no OS4 classic version with stable swap existed)

[Karlos]

OS4 for CSPPC just accepts CSPPC local memory. Motherboad&Zorro memory modules are completely ignored. Joerg Strohmayer decided that Motherboad&Zorro memory support should be dumped in favour of swap memory (even thought no OS4 classic version with stable swap existed)

I wasn't specifically talking about OS4. Z3 RAM is far slower than the local CSPPC memory regardless of whether you're running 3.x, 4.x, MOS or indeed any other operating system that can run on the system.

[freqmax]

Another solution is to use FPGA:s in the manner that fpgaarcade etc.. does. That makes the software the only limit. Ie 32-bit pointers as mentioned earlier.

[the_leander]

Ok i was searching on the internet to find info why the old kv8 max 3 motherboard that has an athlon64 3200+ can handle only 2gigabytes (or 3) of ram while having access to a 64bit processor.Answer was because of the memory controller on the motherboard.

The memory controller for an AMD 64 was onboard the cpu iirc.

Now, the KV8... That'd be a first gen socket 754 using a VIA chipset (I had this board many moons ago).

The socket 939 and later had different memory controllers, which meant that those who had bought into the Athlon64 as early adopters were pretty much SOL after the 3200.

[Franko]

On my A1200 Blizzard 060/PPC, 60Mhz/240Mhz, 256Meg Ram, running OS4.0 is like running an Amiga with only chipmem, it's way too slow.

Is their a minimum CPU type/speed needed to run OS4.0 at a speed that would come close to an A1200 with fast mem, or any hacks or patches that would make OS4.0 run at a useable speed on my set up...

[Kronos]

Theoretically, no existing version of AmigaOS can use more than 4GB of address space, since all pointers are 32-bits wide. Not all of that address space can be RAM either, as you have to map hardware into it too. IIRC, ~2GB is the limit for RAM.

Correction : Some pointers are only 31 bits wide (they are signed and negative values are used as error codes). So the address-space is 2GB, which also has to include onboard components and addons.

[tone007]

On my A1200 Blizzard 060/PPC, 60Mhz/240Mhz, 256Meg Ram, running OS4.0 is like running an Amiga with only chipmem, it's way too slow.

Is their a minimum CPU type/speed needed to run OS4.0 at a speed that would come close to an A1200 with fast mem, or any hacks or patches that would make OS4.0 run at a useable speed on my set up...

Three words: (ok, acronyms) RTG, RTG, RTG.

[Zac67]

OS4 for CSPPC just accepts CSPPC local memory. Motherboad&Zorro memory modules are completely ignored. Joerg Strohmayer decided that Motherboad&Zorro memory support should be dumped in favour of swap memory (even thought no OS4 classic version with stable swap existed)

Somewhat comprehensible - but it'd be much smarter to use currently ignored RAM for swapping - though slow it's way faster than any HDD.

[Karlos]

On my A1200 Blizzard 060/PPC, 60Mhz/240Mhz, 256Meg Ram, running OS4.0 is like running an Amiga with only chipmem, it's way too slow.

You already said you don't have an RTG card. OS4 works on AGA but it wasn't designed for AGA. Having said that, when I did run it on AGA it wasn't that bad (640x512 PAL, 16 colours). Graphics operations weren't noticeably slower than they were on 3.x and some were faster. Overall performance for 68K apps was on par (some better, some worse) than my 040, PPC native apps obviously fared much better. OS4 native versions of PPC apps that worked under 3.x/WarpOS were noticeably quicker too (highlighting the degree to which the PPC is hampered in a primarily 68K OS environment).

Is their a minimum CPU type/speed needed to run OS4.0 at a speed that would come close to an A1200 with fast mem, or any hacks or patches that would make OS4.0 run at a useable speed on my set up...

You need a graphics card. I'm running it right now at 1280x1024 and it's fine. Considerably quicker than the RTG setup was in 3.x on the 040.

[Franko]

Three words: (ok, acronyms) RTG, RTG, RTG.

I've been trying to get hold of a BVision board for years now, but without any luck. The last one I saw on ebay was described as faulty and the guy wanted £150 for it. I don't mind paying silly money to get hold of one but the things are so difficult to find.

Anyone got a BVision for sale, willing to pay a good price for it...