Re: IBM 40G and UDMA. IBM making non workable HDDs?

Re: IBM 40G and UDMA. IBM making non workable HDDs?

[ Follow Ups ] [ Post Followups ] [ FAQ ]
[ Back to Messages ]

Posted by Henry on October 03, 2001 at 18:09:12:

In Reply to: Re: IBM 40G and UDMA. IBM making non workable HDDs? posted by Serge on October 03, 2001 at 06:52:34:

: Thank you, Henry!
: We tried all possible changes available in newest IBM Feature Tools. It was the first our attempt to solve this problem. Nothing. All this HDDs was UDMA100 setting by default. Motherboards BIOS change to UDMA33 got nothing too. But changing IDE cables from 80-pin to "standard" UDMA33 healed this systems. But we want to have normal fast interface... I cant understand this!...
: But anyway thanks a lot!

: : : We have 5 HDD IBM (40G 7200, Model IC35L040AVER07-0) and some different motherboards with VIA Apllo Pro133A, 964, 964T and Intel 815EP chipsets. In UDMA mode ALL of this possible configurations looks very unstable: sometimes HDDs wont recognise at all, sometimes BIOSes reports 8Gb size (five minutes ago it was 40Gb or nothing in same computer). All BIOSes - newest release. But with regular IDE cables (UDMA33) all problems is gone! Please, help! Is it something wrong with IBM UDMA controllers? Looks like IBM HDD absolutly not workable!
: : : IBM e-mail support keeps silence and never answer!
: :
: :
: : Most HDDs are shipped with ATA/66 or ATA/100 disabled so the drives will work with older mainboards. Did you enable high bus speed for the HDDs? the standard IDE cables force operation at ATA/33. IBM should have a utility to change ATA setting; suggest that you try it if you haven't done so already.

Thanks for the feedback - hope you find a way to speed things up. There may not be a big difference in HDD speed - this is a case where the low speed rules. The high speed is mainly useful in the burst mode - that is data transfers made between HDD buffer and the onboard IDE controller. You can see some pretty impressive speeds when your HDD has a large buffer (~2MB) and data transfers are between the buffer and the controller. The sustained speed of most HDDs isn't much higher than UDMA33; overall, there is usually very little difference between UDMA66 and UDMA100 because the controller rate is much higher than the HDD can deliver from/to the platters. If you have a slow component on the same cable as a high speed HDD, the low speed device usually slows everything down. Just remembered - sometimes the 80 wire cables are harder to seat firmly than the 40 wire variety - so make sure all connections are really tight - push the connectors HARD.

Good Luck,

Follow Ups:

Post a Followup

Please note:
  • Messages must be on the topic of this forum!
  • No posting of requests for cracks, codes, serials, or warez!
  • No posting of illegal software or links to such sites!
  • No use of profanity or inappropriate or offensive language!
  • Spamming is not allowed!
  • We track the IP addresses of forum abusers!
  • Abuse of this forum will be reported to your ISP!
E-Mail (optional):
please note: your e-mail address will be visible in your message.



Optional Link URL:
Link Title:
Optional Image URL: