Path: utzoo!news-server.csri.toronto.edu!cs.utexas.edu!sdd.hp.com!hplabs!hpfcso!yoshida From: yoshida@hpfcso.FC.HP.COM (Stuart Yoshida) Newsgroups: comp.windows.ms Subject: Re: Help installing Hyperdisk (was: Norton cache and Windows) Message-ID: <7450005@hpfcso.FC.HP.COM> Date: 6 Mar 91 22:36:34 GMT References: Organization: Hewlett-Packard, Fort Collins, CO, USA Lines: 55 altman@sbstaff2.cs.sunysb.edu (Jeff Altman) writes: >In article <7450004@hpfcso.FC.HP.COM> yoshida@hpfcso.FC.HP.COM (Stuart Yoshida) >writes: >>altman@sbstaff2.cs.sunysb.edu (Jeff Altman) writes: >>> [...] >>> Hyperdisk is not >>> compatible with all drives. This is because it does not use BIOS calls >>> but instead goes directly to the hardware. >>> -- >>> - Jeff (jaltman@ccmail.sunysb.edu) >>> ---------- >> >> I just talked with the author of HyperDisk, and he said, "Hyperdisk >> uses BIOS calls ONLY. It's funny how rumors get started, isn't it?" >> >> So whatever problems HyperDisk has, it's *NOT* because it goes >> directly to the hardware. It does not circumvent the software >> interface protocols; it definitely uses BIOS calls. >>-- >> Stuart > >To quote p84 of the 2/18/91 PC Week: Discussion about why Power Cache >was given highest rating even though Hyperdsk is faster. "The two products >differed not in their performance, but in the compatibility advantage that >Power Cache Plus offers through its use of DOS-file I/O in lieu of the >device specific BIOS-level commands used by HyperDsk." >-- >- Jeff (jaltman@ccmail.sunysb.edu) >---------- The PCWeek review was pointing out was that HyperDisk *does* use BIOS calls, and therefore is somewhat hardware dependent because not all BIOS code is 100% IBM compatible. BIOS calls don't access the hardware directly, but they *do* act on a lower-level than DOS-file I/O calls. This makes HyperDisk sensitive to different flavors of BIOS and therefore somewhat hardware-dependent as the PCWeek review says. Therefore, even though HyperDisk doesn't access the hardware directly, it uses a low-level protocol (BIOS) that is more prone to hardware dependencies. -- Stuart "Every place around the world it seemed the same Can't hear the rhythm for the drums Everybody wants to look the other way When something wicked this way comes." --Jeremiah Blues by STING UUCP: {hp-sdd, hp-pcd, csu-cs, edison, hplabs}!hpfcla!yoshida Internet: yoshida%hpfcla@hplabs.HP.COM VOICE: (303) 229-2324