freePCtech (click here to return to the first page) Search the
    siteHelp on using this siteHome
Forums
Features
Articles
Guides/FAQs
Goodies
Downloads
About
Contact

    Articles / Reviews


IDE - ATA Hard Drive Transfer Rates

by Bob Wright
2002/11/17

IDE - ATA Hard Drive Transfer Rates

Q: I have read about UDMA numbers and ATA numbers in describing the speed of hard drives. I have looked around and find no definite data defining each and how they work. Can you make this more clear?

A: Actually, hard drive speed based on the manufactured structure of the drive is simple to demonstrate. Remember that the speeds expressed are peek transfer rates and in the real world, the average operating speed of the drive will be much less than the peek transfer rate. Here is a listing of the current ATA & UDMA specifications:

Mode max. Specification
PIO DMA
(MultiWord)
UDMA MB/s ATA / 16 ATA / 33 ATA / 66 ATA / 100 ATA / 133
- - UDMA 6 133.0 x x x x
- - UDMA 5 100.0 x x x
- - UDMA 4 66.60 x x
- - UDMA 3 44.40 x x
- - UDMA 2 33.30 x
- - UDMA 1 25.00 x
- - UDMA 0 16.60 x
PIO 4 MW 2 - 16.60
- MW 1 - 13.30
PIO 3 - - 11.10
PIO 2 - - 08.30
PIO 1 - - 05.20
PIO 0 - - 03.30

 

Articles / Reviews

Hardware
  Articles
  Reviews
Software
  Articles
  Reviews
Diagnostics
  Articles
  Reviews
Networking
  Articles
  Reviews
 
Search
 

 

Free PC Tech

Copyright The NOSPIN Group, Inc. 1991-2006.  All rights reserved.