Re: Hard drive larger then 120GB question

July 1, 2007

Gordon Freeman wrote:

> I don't think there's any way you could format a 250GB drive

> with less than 32KB clusters, FAT32 has a limit of how many

> clusters the FAT can contain,

Please have a look at this:

It's a link to a google archived thread in this newsgroup with the

subject:

Cluster size and exploring the limits of FAT-32 Options

As I point out, I've already seen that win-98 can run on a large hard

drive (160 gb, partitioned as a single volume) and with 4kb cluster

size to boot.

FAT-32 does not have to increase cluster-size with increasing volume

size. That is a choice made by the win-9x and ME format tool, to keep

the total number of clusters under 4 million (and in most cases under

2 million).

I believe that strategy was designed so that scandisk could run on a

system with the specified minimum requirements that Microsoft spelled

out for windows 98, which was 16 mb of system memory. Given a system

with that amount of memory, scandisk could not load in a FAT table

containing more than 4 million clusters. Given a system with more

than 4 million clusters (in my case, I've tried up to 40 million) I've

seen scandisk handle a drive scan with no problems (ie - scandisk will

use all available system memory, not just the first 16 mb).

Others say that 4-million cluster limit was rooted in the idea that

Windows must load the entire FAT table as part of it's normal startup

and use, so having a large FAT table would consume inordinate amounts

of available system memory. I countered that argument by saying that

there is no evidence from looking at system memory usage that windows

loads the entire fat table during normal operation, and it really

doesn't have to. It only needs to load the fat entries for the files

that it opens.

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