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Question About SCSI HDs

BigFatCow

Diamond Member
Im thinking about getting a scsi HD and want to know what the difference is between a 68 pin interface and an 80 pin interface?


im thinking about one of the first 4 IBM drives here probally the 36gig version...
 
80pin connectors are also called SCA (single connector ...) and are mainly for server racks that use hot plugin. Theres nothing special about it. The interface includes simply a few pins for the power connection. To get these drives running on a common 68pin scsi cable you need an adaptor - the right adapor for your desired speed (U320,U160,U2W,UW,...)! Generally speaking, the use of adaptors can only introduce problems so it should be avoided. Most drives come in both flavors.
 
Most common cards have a 68 pin connector. 80 pins are for hot-swappable drives in server situations. Note the the 80 pin units come with adapters to 68 pin, not very elegant, but it works.
 
68 pin uses standard LVD cables. 80 pin drives do not use cables but plug directly into a rack. The pins in an 80 pin plug are of different lengths so that they make contact sequentially and may be plugged and unolugged with the power on safely. There are adapters that allow 80 pin drives to be used with 68 pin LVD cables and they work fine. They have been given a bad name by the mal adroits blaming them for their own mistakes. Be sure the adapters you use are certified for LVD.
 
so theres no speed difference? its just allows it to be hot swapable if its 80 pin?

if i get an 80 pin HD and a 68 pin card with the adapter will it still be hot swapable?

and basically i should just get the 80 pin version since its cheaper?
 
No, you should avoid the adapter whenever possible. Regardless, those are bad drives, I wouldn't recommend the the 68pin version either. There's a reason they are so cheap, everyone is trying to offload them.
 
Originally posted by: Pariah
No, you should avoid the adapter whenever possible. Regardless, those are bad drives, I wouldn't recommend the the 68pin version either. There's a reason they are so cheap, everyone is trying to offload them.
huh? Avoid the adapter I agree but there is nothing wrong with the 68-pin connectors.

 
They're hottest and loudest drive released in years, plus they are slow by 15k SCSI standards. Switching to a 68pin interface doesn't fix that.
 
ahh, my bad. I thought you were saying that the 68-pin interface itself is bad, not realizing you were talking about a specific drive model.
 
I have used both 68 and 80 pin drives at work and home for years and like others recommend staying away from adapters. I haven't tried to use any in years but the last time I did they were not cheap either. Something like $20-$40 for each adapter. 80 pins are great if the rest of your system supports them but don't bother with getting adapters.
 
Originally posted by: Pariah
No, you should avoid the adapter whenever possible. Regardless, those are bad drives, I wouldn't recommend the the 68pin version either. There's a reason they are so cheap, everyone is trying to offload them.

they are cheap but the reviews are comparable at http://www.storagereview.com to the seagate lp series,and in most cases edging out the seagate
i use a hdd cooler with mine and it barely gets warm(i can hardly tell a temp difference) noise is no bad except during seeks then it sounds like a rattler but still not that bad to me.
hdtach says i get 52mb per second at 6% cpu utilization which is better than a wd 8mb cache jb drive my friend has by over 10mb a sec.

just to share my numbers-i will agree that the drives have little or no warranty so you are taking a chance on the reliability of ibm drives but mine has been going since oct 15 th bought from this hotdeal

mho ymmv

mike
 
they are cheap but the reviews are comparable at http://www.storagereview.com to the seagate lp series,and in most cases edging out the seagate

Uhh, which Seagate LP are talking about? Certainly not the X15-36LP. Go to the database select any test, then choose the 2 drives and pick compare. The Seagate wins every test. The STR average by more than 10MB/s, access time by 0.7ms, the 4 drivemark's by an average of more than 20%, and the servermarks's by an average of 10%, idle noise by 6.7dB/A(which is quite significant), and temperature by 4.3 degrees Celcius.

hdtach says i get 52mb per second at 6% cpu utilization which is better than a wd 8mb cache jb drive my friend has by over 10mb a sec.

The current gen Maxtor and WD drives both top that by 5-7MB/s.
 
Uhh, which Seagate LP are talking about? Certainly not the X15-36LP
yes

my bad it was the Seagate Cheetah 73LP ST373405LW
i didn't read it right sorry and the other drive it beat was Seagate Cheetah X15 ST318451LW

missed the numbers again sorry

but for half the price you wouldn't consider the ibm's?

also i would have thought that the ibms would have been louder after hearing a few folks griping about the cheetahs so i guess i was just amazed its as quiet as it is,even though louder than a seagate

thanks pariah i will do better reading from now on this is twice you have straightend me out,

thanks

mike

 
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