Date: Tue, 24 Oct 2000 16:39:24 +0200 From: Arild =?iso-8859-1?Q?Eiken=E6s?= Vengen <arild.vengen@erasmus.uib.no> To: freebsd-hardware@FreeBSD.ORG Subject: Re: Promise Ultra-ATA100 vs FastTrak 100 Speeds Message-ID: <39F59F1C.A31756E8@rasmus.uib.no>
next in thread | raw e-mail | index | archive | help
Steve Coles wrote: > There has been a lot of press that these are the same cards, and I > seem to remember that FreeBSD treats the FastTrak as just an IDE > controller, so can anyone enlighten me on the vast speed differential > between the two: <snip> > Summarised Results > ------------------ > 1) One drive alone (no ccd) reads and writes at 30 Mb/Sec > 2) Ultra 100 reads and writes at 29 MB/sec > 3) FastTrak 100 writes at 50 MB/sec, reads at 48 MB/sec > 1) Why is the Ultra so slow ( constructive answers only please :) ? The only thing I can think of is that the Ultra 100 isn`t utilizing the udma/100-channel, and falls back to udma/33, since both reads and writes are at 29MB/sec witch is just maxing out the udma/33-standard. When running my IBM 75GXP off of an udma/33-controller (BX-chipset) I never get more than 29MB/sec, never 31 or 32MB/sec. I seem to remember something about the udma/66-versions from Promise (both RAID and non-RAID) was the same card (with a different BIOS), but I thought the udma/100-versions had more differences. Arild. To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-hardware" in the body of the message
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?39F59F1C.A31756E8>