Eric Bosco (ebosco@us.oracle.com) wrote:  [ First of all, please edit your postings.  Wading through 50 lines of   quoted crud, which people have already read, makes people much less   likely to help you.  Of course, if you don't want to be helped, that's   your problem.  ;-) ]  > Is this true??? I was under the impression that people on the net had both   > SCSI and IDE working together.       No, it's not true.  You can get SCSI and IDE to work together, but there are restrictions (at least with the Adaptec 1542):  * You MUST boot from the IDE drive.  There is no way to boot from the   SCSI drive if you have both IDE and SCSI drives.  * You MUST disable the SCSI ROM BIOS (I'm not sure about this, though),   and so you must also use some special drivers to access the SCSI   drive.  (Hmm.  I know that you have to disable something related to   the SCSI BIOS, but I'm not sure if it is the ROM itself.)       Back in February, someone asked about IDE and SCSI (this question gets asked again and again).  At the end of this message, I've included an edited copy of my reply.  You might find it interesting.       -- Darryl Okahata 	Internet: darrylo@sr.hp.com  DISCLAIMER: this message is the author's personal opinion and does not constitute the support, opinion or policy of Hewlett-Packard or of the little green men that have been following him all day.  =============================================================================== > 1)  Is it worth it to get SCSI over IDE?   Will there be a noticable >     decrease in access time/increase in Xfer rate?       For MSDOS applications, ISA-based SCSI and IDE controllers generally have comparable throughput.  You might get slightly higher throughput with a SCSI disk, but you'll also pay more for the disk ($30-$100 and up, in some cases).  You'll also pay much, much more for a good SCSI controller.       Note that good SCSI controllers really show their power if they're used with a good multitasking operating system (like a PC Unix). Unfortunately, neither MSDOS nor Windows 3.1 is a good multitasking operating system.  The performance advantage of SCSI controllers is mostly wasted with these, which leaves the advantage of being able to connect multiple devices to the SCSI bus as the only advantage. However, note that you can expect to pay a premium for SCSI devices.       If you're only going to be using MSDOS, stick with IDE.  It's cheaper, and you'll have less headaches.  > 4)  Will virtually any SCSI device chain into the controller for my >     hard-drive (bernoulli box, CD-rom, Tape Drive, etc).  [ Note: the following is true for MSDOS/Windows only.  Who knows what   the future holds for Windows NT and Unix??? ]       No.  Generally, you have to find drivers for each SCSI device, which probably don't exist unless you're using one of the "better"/"high performance" SCSI controllers.  These are typically bus-mastering SCSI controllers that cost around $180-$400 (street prices) and up, and drivers that allow you to connect these controllers to popular name-brand SCSI devices either come with the card, or can be purchased (for under $100 list price).  Examples of such driver kits are:  * Adaptec's EZ SCSI kit (list: $75).  This works only with Adaptec SCSI   controllers.  * CorelSCSI! (from the same people who make CorelDRAW!) (list: $99 (?)).   This driver kit will supposedly work with any SCSI controller card   that has an ASPI driver, like the Adaptec.       Central Point's PC Tools for DOS 8.0 supports a number of SCSI tape drives (the documentation lists 40 tape drives).  Unfortunately, it works only with Adaptec controllers.  > 5)  Are there likely to be other problems/incompatibilities with a >     SCSI controller and  sound cards/video accelerators/and similar >     equipment.       Yes, you will run into problems, if you're using a high-performance, bus-mastering SCSI controller.  This doesn't sound right, doesn't it?  It's true, though.  With one of these controllers, you'll probably have to tweak your system to get it to work with sound cards, floppy-controller-based tape drives (like the CMS Jumbo 250), and Windows 3.1.  I know.  I've been to h*ll and back getting my SCSI controller to work with various hardware/software (thank God for tape backups).  If you want a copy of my "Adaptec 1542 hints and tips" file, send email.       These problems aren't really the fault of the SCSI controller card; the problems are really with the general hardware and software design of the PC (e.g., no standards).  However, adding a bus-mastering SCSI card is what brings these problems to the surface and makes them visible.