Why a SCSI cd rom drive?

[Bmxpunk86pl]

Yea since like 52x cdrom drives go at 7megs a sec (around there) and ata33 goes at 33megs a sec and scsi goes way faster than that, why would u spend the extra money on a scsi cdrom drive when it wount even overwhelm the speed of ata33?

[Monaco]

hmm, that IS a good question!

Maybe if you have serious CDROM storage needs, like a system with 12 CD drives constantly being accessed. A CD server or something. Beyond that I can't think of anything. SCSI just ain't worth it anymore unless you are doing really heavy-duty stiff.

[sfa ok]

Probably if you don't have any spots on your ide controller left? Or have an all-scsi system, like my old 486 was! :D

[SpeeDj]

Well coming from a guy who runs a full SCSI Plextor combo *A UltraPlex 40X CD Rom and a PlexWriter 8X/20 CD-R* I can say honestly SCSI is better in the matter of data tranfer it has the ability to handle reading and writing at the same time with minimal performance hit's. That is why when you buy an IDE Burner and CD/DVD Rom they don't recommend running them on the same chain if you intend on direct cd copy, they recommend completely seperating the drives IE one on primary ide channel and one on secondary ide channel. That is just what I have heard, and can honestly say my plex combo has worked always fabulously. Plus what other way are you going to run up to Seven devices on one chain ? SCSI has it's merits, speed race wise yeah it is hard to justify a U160 SCSI Setup vs a ATA133 Setup, but alot have forgotten IDE's limitations of only two devices per chain.

J

[Bmxpunk86pl]

oh ok, thanks guys

[Monaco]

That is why when you buy an IDE Burner and CD/DVD Rom they don't recommend running them on the same chain if you intend on direct cd copy, they recommend completely seperating the drives IE one on primary ide channel and one on secondary ide channel.

Why do they say that, anyway? I mean, thanks to DMA shouldn't there be no problems? I have my CDRW and regular CD drive on the same channel without difficulties. Am I just lucky?

[dugans]

Frequently they will run fine; I've had mine on the same channel as well, but SpeeDj is right!

I have two systems running all scsi (Adaptec 2940 and 3940, great cards), I don't have any drives that are up to date, but scsi allows me to run a bunch of old scsi drives that I got free and still get 8 or 10 gigs of space. And have cd roms. And the only thing I had to pay for was the cards! (Bought used and cheap of course!)

Incidentally: even with very old scsi drives, performance is good: no benches because both pcs are running linux now but trust me: scsi does ROCK!

If I had an unlimited budget to build 1 pc there is no doubt in my mind that IDE devices would NOT be allowed in the thing.

[Bmxpunk86pl]

Ok how much would it be fore a scsi setup up with 8 gig harddrive, cabel, terminator,card? Dont know what type of scsi. WOuld i aslo be able to use ide and scsi at the same time?

[Monaco]

Frequently they will run fine; I've had mine on the same channel as well, but SpeeDj is right!

SO- mine run fine like that, my folks' box runs fine like that, yours runs fine like that- but it doesn't work? :eh?:

Looks like problems are actually kinda rare. What kind of problems can be caused, anybody know? Is it only during a direct CD-to-CD copy?

BMX- yah, you can mix IDE and SCSI drives in the same system as I recall. Been a while since I tried.

[Shadow ÒÓ]

Originally posted by Bmxpunk86pl
Ok how much would it be fore a scsi setup up with 8 gig harddrive, cabel, terminator,card? Dont know what type of scsi. WOuld i aslo be able to use ide and scsi at the same time?

I see used drives on ebay for $50 and you can pay anywhere from $150 to $1000 for a controller.

Only new drives I saw on pricewatch were 30ish gigs (or bigger) for $150.

yes....you can use IDE and SCSI at the same time.

[donny_paycheck]

Also, you'll never find 10 or 15k RPM drives for ATA133. The access times of a Cheetah are like 3.5ms!

[It_The_Cow]

Originally posted by Monster of Rock
SO- mine run fine like that, my folks' box runs fine like that, yours runs fine like that- but it doesn't work? :eh?:

Looks like problems are actually kinda rare. What kind of problems can be caused, anybody know? Is it only during a direct CD-to-CD copy?Usually, no problems are caused by this sharing. You can have them on the same channel, but supposedly, it hinders the performance a bit. This is so since the the data can only travel in one direction. This is usually for on-the-fly copying. Data must be sent from the CDROM to the CPU, then from the CPU to the CDRW. If it were on two seperate channels, the data can be sent to the CPU and then sent to the CDRW while still having a constant stream of data from the CDROM. I personally don't care much for the performance gains, so I keep mine on the same channel as well

[Monaco]

thanks It_, that's what I thought.

One nitpick- if you enable DMA transfers on both drives, they should be able to 'talk' to each other without hitting the CPU at all. I think! Maybe my understanding of DMA is flawed.

ahh, whatever, I'm just going to try it both ways now and see what happens!:D