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Amiga computer related discussion => Amiga Hardware Issues and discussion => Topic started by: Marcb on September 23, 2008, 07:56:59 AM

Title: 4gb Limit
Post by: Marcb on September 23, 2008, 07:56:59 AM
Hi,

I'm a little confused...
I've read through all the relevant posts but I'm either too dumb to see it or it hasn't been mentioned:

Is the 4gb HD limit a limit per HD/CF card or an overall machine limit? I.e if I have two 4gb CF cards with 3 partitions each (all below 2gb) am I able to safely use the two with FFS?
I assumed that because it is an addressing limitation the limit applied to each physical device, am I wrong?

Cheers,

Marc
Title: Re: 4gb Limit
Post by: rkauer on September 23, 2008, 08:03:25 AM
 The limit is for each physical device, so don't worry.
Title: Re: 4gb Limit
Post by: Thomas on September 23, 2008, 08:05:49 AM

The limit is per HDD. It is completely safe to have multiple HDDs with 4GB each.

Bye,
Thomas
Title: Re: 4gb Limit
Post by: Marcb on September 23, 2008, 09:13:54 AM
Thank you gentlemen!

I
Title: Re: 4gb Limit
Post by: weirdami on September 23, 2008, 11:56:30 AM
so you can't have 100 partitions of 4gb size on a single 400gb hard drive? if you could, someone should write some kind of utility to handle files across the multiple partitions so that it acts like a single partition as far as the user is concerned.
Title: Re: 4gb Limit
Post by: pVC on September 23, 2008, 02:28:51 PM
Quote

weirdami wrote:
so you can't have 100 partitions of 4gb size on a single 400gb hard drive?


No, as stated the 4GB limitation is PER HD. And the other important limitation to remember is 2GB limitation per partition.

That means you can have practically as many partitions as you want on HD until they are all smaller than 2GB each and total usage of the HD will be under 4GB.
Title: Re: 4gb Limit
Post by: rkauer on September 23, 2008, 03:06:20 PM
Quote

pVC wrote:
Quote

No, as stated the 4GB limitation is PER HD. And the other important limitation to remember is 2GB limitation per partition.

That means you can have practically as many partitions as you want on HD until they are all smaller than 2GB each and total usage of the HD will be under 4GB.


 Not true, either.

 Going out the scope of the question: you can use any HD up the Petabytes!!! (to be released some day), but without a lot of patches the Amiga will not even boot.

 Check this site (http://www.youngmonkey.ca/nose/articles/NewTekniques_9810/AmigaInMotion.html) for more information on the 4Gb barrier.

 And remember to patch the SCSI.device itself to use a HD with more than 127Gb.;-)
Title: Re: 4gb Limit
Post by: ZeBeeDee on September 23, 2008, 03:15:52 PM
@ rkauer

We like that link very much ... a very good explanation!  
Title: Re: 4gb Limit
Post by: Jupp3 on September 23, 2008, 03:43:36 PM
I think it's a good idea to point out that NDS isn't the only solution to the problem. Another common one is TD64 (which I prefer). There used to be big flamewars over the two systems, you can probably find them somewhere, if you want to read comments about them.

In addition some hardware have their custom solutions. Elbox Power Flyer for example can be configured to split >4GB HD's into max 4GB units. That way you shouldn't have any problems even with software that directly accesses HD (such as many older disk salvage programs, Fusion etc.)
Title: Re: 4gb Limit
Post by: pVC on September 23, 2008, 06:16:36 PM
Quote

rkauer wrote:

 Not true, either.

 Going out the scope of the question: you can use any HD up the Petabytes!!! (to be released some day), but without a lot of patches the Amiga will not even boot.


But wasn't the question how the 4GB limit works? Not the solutions IF you want to use more :) Kept the discussion on topic I thought this was about :)
Title: Re: 4gb Limit
Post by: Thomas on September 23, 2008, 07:00:39 PM
Quote
And the other important limitation to remember is 2GB limitation per partition.


There is no such limit.


Quote
Not true, either.

Going out the scope of the question: you can use any HD up the Petabytes!!!


With the currently available patches and softwares drives bigger than 2 TB will not be recognised. (2^32 blocks of 512 bytes each.)


Quote
but without a lot of patches the Amiga will not even boot.


If it does not boot without patches, then it won't boot with patches, either. At boot time the only driver available is the one in Kickstart. If it is not able to boot the HDD, then patches cannot be applied and booting is not possible.


Quote
And remember to patch the SCSI.device itself to use a HD with more than 127Gb.


It's 128 GB. And you don't need a patch to connect and use bigger drives. The system will only crash if you create partitions above the 128 GB border. And you can disable the crashing partition in the early startup menu.

Bye,
Thomas