Ultra ATA / UDMA - whats the best?

[DogFacedKilla]

Im looking at hd's and I am wondering what the difference is between a Ultra ATA interface and a UDMA interface, (there is also an ATA but I'm just assuming it is inferior to the ultra... cus ultra means better ). Which is faster and best for a performance oriented machine?

Also, what do the numbers after Ultra ATA drives mean (ie; 133, 100, 66...)?

Thanks,

-Dan

<font size=-1>[ This Message was edited by: DogFacedKilla on 2002-04-06 15:00 ]</font>

[murray]

It's Ultra ATA, not ADA (don't remember what it stands for). UDMA and UATA are just different ways of referring to the same spec I think. The 33, 66, 100, 133 business refers to the throughput limit in MB/s of the controller. As long as you have at least ATA 100, you don't need to worry about the hard drive exceeding the bandwidth (unless you're running a decent sized RAID). If I remember correctly, pretty much all ATA based hard drives will function with any of the ATA standards. Such that if you had that Maxtor D740X I mentioned (an ATA133 drive), it would still work fine on a motherboard that only supported up to ATA100. You also probably wouldn't see much, if any performance loss. The compatability thing works the other way around too.

I'm pretty sure the performance nuances will depend more on which drive you get and which EIDE controller the motherboard uses than on whether the standard is ATA100 or ATA133.

[DogFacedKilla]

hehe, thnx... dunno where I got that ADA bit from

Anyhow, yea I like the maxtor drives, im thinking of going with the 40 gig D740x (ATA 133, 7200rpm) - its a hundred dollars or so cheaper, and for my purposes 40 gigs will last me for awhile.

-Dan

[murray]

Newegg.com has Maxtor drives pretty cheap (hell, they've got a lot of stuff cheap), and they're well liked by a lot of people on this forum.

This is their Maxtor section.

[MaceMan]

This might help. The UDMA section of data was ripped from someone's reply from the forums earlier... though I don't remember who posted it.

Harddrives
ATA-1 PIO Mode 0; 3.3 MB/s
ATA-1 PIO Mode 1; 5.2 MB/s
ATA-1 PIO Mode 2; 8.3 MB/s
ATA-2 PIO Mode 3; 11.1 MB/s
ATA-3 PIO Mode 4; 16.7 MB/s
ATA-4 UDMA; 33 MBps
ATA-5 UDMA/66, UDMA/100

UDMA 0 = 16MB/s (same as PIO Mode 4)
UDMA 1 = 25.5MB/s (very rare)
UDMA 2 = 33MB/s
UDMA 3 = 44.4MB/s (very rare, never saw any of these)
UDMA 4 = 66MB/s
UDMA 5 = 100MB/s
UDMA 6 = 133MB/s