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mousehouse · Nov 28, 2003, 05:24 AM

hi,

i've got an iMac/15 USB2.0 on order at Apple and was wondering what the maximum HD size would be that it can take... the link from my other thread to apple-history.com says it has an ATA/100 controller - what maximum size does it correspond to?

TIA

Dex13 · Nov 28, 2003, 01:46 PM

I believe it is 160 gb but I may be wrong ...

Krusty · Nov 28, 2003, 04:57 PM

Your question made me curious as well. I haven't found the official specification for ATA-100 yet but I DID find several of the first generation 250mb hard drives listed as ATA-100. So ... at least 250 so far

mousehouse · Dec 1, 2003, 08:51 AM

i've actually found out the following according to the standards committee (http://www.t13.org),

up until ATA66 there were only 28 bits for addressing blocks on the drive (of 512 bytes), which makes 128Gb (or approx 137.000.000.000). now, with either ATA100 or ATA133 this changed to 48 or 64 bit addressing (didn't find that).

the only influence left now is the way it's implemented in the hardware. eg. there are ATA100 PC's that don't work with >128Gb drives.

reading apple's spec on the new iMac's (USB2.0) there is an ATA100 controller in there. concluding from the drive size available as BTO (160G) this would suggest that there is a lot of addressable HD space in that iMac...