Are external drives subject to 32-bit LBA restrictions? 1

[cyberspace]

I am going to be upgrading the hard disk on a guy's PC and it's a 5 year old machine, currently with a 9.5gb HDD in it. I plan to put in a 120GB disk so as not to encounter and lba related issues (and i don't want to mess with the bios), but just as a matter of course I was wondering if these issues apply to USB external drives also?

I've googled but not getting much useful information.

Thanks.

'When all else fails.......read the manual'

 

[cdogg]

First of all, it's not 32-bit LBA. Old and outdated PC's use 28-bit LBA which has the 137GB restriction. However, newer PC's use 48-bit LBA which has an upper limit of 144 petabytes (144 million GB).

You can read more about it at:

http://www.48bitlba.com

Also at that site, I found an answer to your question in the FAQ section about USB hard drives:

http://www.48bitlba.com/faq.htm#FAQ10

Apparently, it doesn't apply to USB external drives like it does to internal ATA drives. Keep in mind, however, that USB 2.0 (60MB/s) and Firewire (50MB/s) is slower than internal ATA/100. A hard drive only averages 40-45MB/s, but it can occasionally peak well above 70MB/s which factors into a higher average. USB 2.0 and Firewire drives are fine for storage, but it isn't recommended for running the operating system or program files.

Also since you're talking about an older PC, it won't have USB 2.0 integrated on the motherboard. You would have to purchase a PCI USB 2.0 card which doesn't usually run at full speed (since it's sharing the entire PCI bus with other devices).

~cdogg
"Insanity: doing the same thing over and over again and expecting different results." - Albert Einstein
[tab][navy]For general rules and guidelines to get better answers, click here:[/navy] faq219-2884

 

[bcastner]

Great answer.

Thanks cdogg.


____________________________
Users Helping Users

 

[cdogg]

Hey there Bill. I see you're still quite lively here in the XP forum. Thought for a while there you left the site altogether!

Thanks for the star I suppose, but you know it's not necessary!!


~cdogg
"Insanity: doing the same thing over and over again and expecting different results." - Albert Einstein
[tab][navy]For general rules and guidelines to get better answers, click here:[/navy] faq219-2884

 

[cyberspace]

Pro explanation, thanks! Funny thing is i know it's 28bit, don't know why I wrote 32 lol.

Incidentally I had read that site you mentioned, obviously didn't read it well enough though.

Yes I didn't really consider USB to be the best idea for the reasons you outlined, I was just wondering really, incase he deiceded he wanted a huge disk!

Thanks again.

'When all else fails.......read the manual'