SCSI vs SATA

[R. McCarty]

After years of using primarily SCSI drives, I finally decided to move on
to more modern technology. I had been using Ultra-160 SCSI drives on
an Adaptec 19160 controller. Unfortunately, over the past month or so
I have had two Seagate SCSI Cheetah drives to go bad on me.
My Intel motherboard has two SATA controllers, so I checked around
for some inexpensive SATA drives. Our local Tiger Direct Outlet was
offering some Hitachi 40.0 Gigabyte drives for under $50.00. Just 7200
RPM with an 8-Meg cache. Spec's for the drive had access time at 9.0
mSec and average throughput at 61.0 Megabytes per second.
Decided to test out SATA and re-configure my PC for probably the 100+
time. Imaged all the partitions to a "Tray" IDE drive, for quick cut-over.
Replaced 3-SCSI's with two Hitachi 7K250's and replicated the images
back to the SATAs.

Overall, I must say I'm impressed. Both SATA drives are delivering an
average throughput of 59.3 Megabytes a second. The access time is a
bit poor at 16.9 mS (Compared to 8.6 with SCSI). However, at 7200
verses 10,000 & 15,000 RPM the SATA keep up pretty well. The point
of this post is just to illustrate how you can get into a mindset that only
a
certain technology will meet your needs. Will I miss the SCSI access times,
probably. What I won't miss is the $250+ price on a Ultra 160/320 disk.
Or for that matter, the acoustic whine of those 10-15K RPM drives.My
PC now sounds like it's off, I can only hear the front intake fan. From a
thermal standpoint, there isn't much difference. The case temp is staying
right at 109 F. One thing that's nice, is the SATA drives report their temp
to Everest, where the SCSI drives didn't.

So far I can't really tell much difference in overall performance, a few
things "lag" a little bit compared to the SCSI setup. Anyway, thought I'd
take a few minutes to post up the results.

 

[Gary Davis]

You should check out the Maxtor RAPTOR drives. Only 74gig but 10,000rpm and
very very fast.

 

[R. McCarty]

You're probably right. It's just I've used SCSI for so long, I was really
just "Putting a toe in the water first". I did check on the Raptors, I like
the fact they utilize Command Queuing. I didn't want to budget too
much cash for this first attempt. Plus, I've read that SATA-II is coming
and will push the bandwidth up to 300 Meg. Suppose, when Dual-Core
CPUs appear, I may update my primary rig and go with higher end
SATA drives at the same time. Anyway it was a good exercise to see
real world comparison between SCSI and SATA.

 

[David H. Lipman]

From: "R. McCarty" <[email protected]>

| After years of using primarily SCSI drives, I finally decided to move on
| to more modern technology. I had been using Ultra-160 SCSI drives on
| an Adaptec 19160 controller. Unfortunately, over the past month or so
| I have had two Seagate SCSI Cheetah drives to go bad on me.
| My Intel motherboard has two SATA controllers, so I checked around
| for some inexpensive SATA drives. Our local Tiger Direct Outlet was
| offering some Hitachi 40.0 Gigabyte drives for under $50.00. Just 7200
| RPM with an 8-Meg cache. Spec's for the drive had access time at 9.0
| mSec and average throughput at 61.0 Megabytes per second.
| Decided to test out SATA and re-configure my PC for probably the 100+
| time. Imaged all the partitions to a "Tray" IDE drive, for quick cut-over.
| Replaced 3-SCSI's with two Hitachi 7K250's and replicated the images
| back to the SATAs.
|
| Overall, I must say I'm impressed. Both SATA drives are delivering an
| average throughput of 59.3 Megabytes a second. The access time is a
| bit poor at 16.9 mS (Compared to 8.6 with SCSI). However, at 7200
| verses 10,000 & 15,000 RPM the SATA keep up pretty well. The point
| of this post is just to illustrate how you can get into a mindset that only
| a
| certain technology will meet your needs. Will I miss the SCSI access times,
| probably. What I won't miss is the $250+ price on a Ultra 160/320 disk.
| Or for that matter, the acoustic whine of those 10-15K RPM drives.My
| PC now sounds like it's off, I can only hear the front intake fan. From a
| thermal standpoint, there isn't much difference. The case temp is staying
| right at 109 F. One thing that's nice, is the SATA drives report their temp
| to Everest, where the SCSI drives didn't.
|
| So far I can't really tell much difference in overall performance, a few
| things "lag" a little bit compared to the SCSI setup. Anyway, thought I'd
| take a few minutes to post up the results.
|

So basically the SATA are on par with Ultra 160. I use Ultra 160 and was interested in
throughput on SATA. Thanx for the info. It is obvious that SATA is less expensive than
SCSI. Most of my devices are SCI (Tape, CD, CDR, CDRW and hard disks) I was dismayed at the
fact I couldn't find a DVDRW SCSI drive. I did get a HP 420i and generally pleased with it
and it is the "only" IDE device on my main system.

I appreciate your posted results.

 

[Guest]

I think of SATA as the cheap SCSI. The drives are fast, but not as fast as
the current SCSI drives. The main advantage of the SCSI drives is the
ability to mark bad sectors on the fly and the amount of sectors that it can
remap before it needs to be replaced. SCSI allows for a lot of errors before
it will fail entirely. But in the home, who cares. SATA is great for the $$$

-Nate

 

[DevilsPGD]

In message <[email protected]> "Nate"

I think of SATA as the cheap SCSI. The drives are fast, but not as fast as
the current SCSI drives. The main advantage of the SCSI drives is the
ability to mark bad sectors on the fly and the amount of sectors that it can
remap before it needs to be replaced. SCSI allows for a lot of errors before
it will fail entirely. But in the home, who cares. SATA is great for the $$$

No -- The main advantage of SCSI over SATA is that you can connect
multiple drives to one controller.

Bad sectors can be marked on the fly by the file system, so this isn't a
significant problem with a modern file system.

 

[Don Schmidt]

In message <[email protected]> "Nate"


No -- The main advantage of SCSI over SATA is that you can connect
multiple drives to one controller.

Bad sectors can be marked on the fly by the file system, so this isn't a
significant problem with a modern file system.

 

[Guest]

Hmm. I seem to recall my controller having 4 ports on it. I also seem to
recall my server having 12. I also seem to recall how you are wrong. SCSI
drives have the ability to remap bad sectors on the fly, a feat not available
on any other drive to date. The drives reserve a certain amount of space on
the platters for remapping those bad sectors to. With WindowsXP, when you
have a bad sector you need to reboot to the recovery environment and run
chkdsk /r.

Don't be so quick to respond when you have no idea what you are talking about.

-Nate