IDE vs SCSI, dma66

[Ygor]

I have an Abit bx6-r2 and a WD drive that's capable of udma66. I have just 2 pci slots left & would like to add a cd-rw but am also considering a promise card to utilize the dma66 speed.
I understand the thruput with scsi is greater than with ide, but by how much? I'd also like to burn music cds as well as data cds. (a former roomate had at least one friend who felt he needed my cds worse than I did)
So... will scsi with an adapter make more sense than a dma66 card, are both good investments, or neither?

[Dominus]

SCSI has many formats, and their bandwidth ranges from 40mbps for SCSI, all the way up to 120mbps for U3WSCSI. Unless you have enormous ammounts of money to burn, you might as well stick with the UDMA66 card with a 7200rpm drive. SCSI drives are awesome pieces of hardware, but they can range up to $1000 for 1 drive at 9.1GB and 10000rpms.

For burning CDs, remember that there are lots of good IDE CDRs that are a lot cheaper than their SCSI counterparts. I have a HP8100 CDRW (IDE) that has never let me down. SCSI burners are capable of a lot higher speeds, and will give you less buffer-underrun errors, but if you have a nicely tuned system, an IDE burner is just as good in my opinion.

Theres a lot more to be said on this topic, so jump in guys!

[Stan]

Ygor,

I had the same dilemma 2 months ago... SCSI or not SCSI, that is the question...
One problem of SCSI is the price... very expensive.

Then, I remembered seeing a RAID IDE controller card somewhere on the web. It is the Promise FastTrack RAID. There is a UDMA66 version.

So, I made the choice to buy the card, 2 new HD (IBM 22Gxp, 9.1Gb, 7200rpm, 2Mb cache) and set up this system as RAID0 (striping).

According to some benchmarks, this disk sub-system is faster than a single SCSI U2W HD (check this link for the benchmarks www.sysopt.com/forum/Forum1/HTML/001130.html (http://www.sysopt.com/forum/Forum1/HTML/001130.html) ).

One drawback: IDE is more CPU intensive than SCSI. That means that when you will use your CD-RW on a IDE PC, all the resources will be "eaten" by the burning process. Therefore, the PC will be unusable during that process.
This does not happen on a SCSI PC.

When you consider the difference in prices, I believe that SCSI is not worth it !
The FastTrack and two 9.1Gb cost me 330 UK pounds. If I had bought a SCSI controller (Adaptec 2940U2W) and a ibm 9LZX U2W, I would have paid 600 UK pounds !!!!! for only 9Gb of space !!!! and lower performance !!!

One last thing, the FastTrack controller co-exists with the existing onboard controller. You can have 2 FastTrack controllers in your PC and, why not, set up a stripe of 8 HD !

Stan

[This message has been edited by Stan (edited 09-17-99).]

[FastEddie]

One of the other major benifits of all scsi concerns system resources. Four IDE devices eats two irq's, while you can run up to seventeen devices on an U2W scsi bus using only one irq.

Just my .02
FastEddie

[Ygor]

hmmm If I must go all the way and use scsi hdd(s) to realize the benefit with scsi on the cd-rw, I'll stay with IDE. That's just too much to lay out at one time.

I saw your thread about the Promise Raid0 setup before Stan. I'd hoped to add up to a 20 gig drive in the next year or so. My existing dma 66 capable drive is 9.1 and I am happy with my Maxtor 11.5 as a slave now. Not sure I really need that much drive space, just am a data pack-rat, hate to lose anything I might need to refer to later. I'd actually lose a gig or so doing that. Also there's a rumor of dma 100 about the end of this year... But that's another thread!

Thanks all!