Re: 68 pin vs. 50 pin SCSI HD?
> SCSI was a great interface in it's day. SCSI over fiber and other serial channel transport means are still in wide use. -- You received this message because you are a member of G-Group, a group for those using G3, G4, and G5 desktop Macs - with a particular focus on Power Macs. The list FAQ is at http://lowendmac.com/lists/g-list.shtml and our netiquette guide is at http://www.lowendmac.com/lists/netiquette.shtml To post to this group, send email to g3-5-list@googlegroups.com For more options, visit this group at http://groups.google.com/group/g3-5-list
Re: 68 pin vs. 50 pin SCSI HD?
All SCSI-II and SCSI-III wide drives are supposed to be backward compatible, but may require a jumper to be set differently. I have several adapters that convert the 80pin SCA drives to be able to use both the 50pin, or 68pin cables. With SCSI, the slowest drive, or device on the chain (cable) determines the maximum speed that the chain can run at, so if you have slower SCSI-II, or SCSI-III wide drives on a cable that also has a SCSI-I 50pin device, the faster device will be slowed down to the max. speed of the slower device. I have an over-clocked Amiga A4000 that can no longer use it's SCSI controller, because of timing issues. But I have another RAM expansion board that has a fast SCSI-II controller that I can use instead of the SCSI controller on the Amiga accelerator, so I am happier to keep the accelerator over-clocked at 60% faster operation and give up the accelerator's built-in SCSI controller. SCSI has much less CPU overhead than IDE, which can make direct speed comparisons misleading, as all good operating systems are now Multi- tasking, Multi-threaded, so when copying large files, or loading them to RAM to run while also doing other things on your computer, using a SCSI drive will allow a great deal more CPU resources for the other tasks, where an IDE drive will not. As most computers are far more powerful today than is needed for most software, this is not an issue often. Back in the days of 30MHz CPU's instead of 3.0GHz CPU's with multiple cores, using a SCSI drive could make more of a difference. At least on an Amiga, which was one of the first popular home computers that pioneered Multi-tasking. I remember impressing Windows users by formatting up to 4 floppy disks at the same time while playing a 4 voice music mod and using a high color paint program all at the same time on a 7MHz computer that reacted faster than their 286 systems running at 16MHz or 20MHz. Ahhh, the good old days! SCSI was a great interface in it's day. On Dec 10, 2011, at 4:54 PM, Barry Levine wrote: Hi One of the 8GB SCSI HD's on my 8600 G3 is failing. Checking around eBay, I see 68 pin SCSI HD's for sale; and one can purchase an adapter to go to the mac 50 pin cable. I also noticed that there are many larger size 68 pin scsi HD's around than the 50 pin - are these 68 pin drives a bit more recent than the 50 pin ones, and are they usable in my mac with the adapter? thanks Barry -- You received this message because you are a member of G-Group, a group for those using G3, G4, and G5 desktop Macs - with a particular focus on Power Macs. The list FAQ is at http://lowendmac.com/lists/g-list.shtml and our netiquette guide is at http://www.lowendmac.com/lists/netiquette.shtml To post to this group, send email to g3-5-list@googlegroups.com For more options, visit this group at http://groups.google.com/group/g3-5-list
Re: 68 pin vs. 50 pin SCSI HD?
Thanks, good info. Barry > On Dec 10, 2011, at 7:54 PM, Barry Levine wrote: > >> Hi >> >> One of the 8GB SCSI HD's on my 8600 G3 is failing. Checking around eBay, >> I >> see 68 pin SCSI HD's for sale; and one can purchase an adapter to go to >> the mac 50 pin cable. >> >> I also noticed that there are many larger size 68 pin scsi HD's around >> than the 50 pin - are these 68 pin drives a bit more recent than the 50 >> pin ones, and are they usable in my mac with the adapter? >> >> thanks >> >> Barry > > 68 pin is wide scsi. 16 bit data path vs the 50 pin's 8 bit. Drives might > be slightly newer, but check the individual drives. > > You may also want to look onto 80 pin SCA scsi. These are server drives > and the sca adapters are also easy to get.. Generally more robust than the > 50 and 68 pin drives. Also hotter, larger capacity , noisier and faster > than most 68 and 50. > > Depending upon how much storage you need, the 73Gb SCA drives seem to be > the sweet spot. 10k rpm drives are starting at $20 shipped. You can > ignore the tray that is included with many. That is what they used to > install them in the server. Just remove the 4 screws and mount it in your > Mac. > > The one thing to be careful of is formatting. Many SCSI drives are not > included in Apple's Drive SetUp program. There are hacks to get it to > recognize "non-supported" drives. Or a 3rd party drive utility like LaCies > will format most any SCSI drive. > > Len > > > > -- > You received this message because you are a member of G-Group, a group for > those using G3, G4, and G5 desktop Macs - with a particular focus on Power > Macs. > The list FAQ is at http://lowendmac.com/lists/g-list.shtml and our > netiquette guide is at http://www.lowendmac.com/lists/netiquette.shtml > To post to this group, send email to g3-5-list@googlegroups.com > For more options, visit this group at > http://groups.google.com/group/g3-5-list > -- You received this message because you are a member of G-Group, a group for those using G3, G4, and G5 desktop Macs - with a particular focus on Power Macs. The list FAQ is at http://lowendmac.com/lists/g-list.shtml and our netiquette guide is at http://www.lowendmac.com/lists/netiquette.shtml To post to this group, send email to g3-5-list@googlegroups.com For more options, visit this group at http://groups.google.com/group/g3-5-list
Re: 68 pin vs. 50 pin SCSI HD?
On Dec 10, 2011, at 7:54 PM, Barry Levine wrote: > Hi > > One of the 8GB SCSI HD's on my 8600 G3 is failing. Checking around eBay, I > see 68 pin SCSI HD's for sale; and one can purchase an adapter to go to > the mac 50 pin cable. > > I also noticed that there are many larger size 68 pin scsi HD's around > than the 50 pin - are these 68 pin drives a bit more recent than the 50 > pin ones, and are they usable in my mac with the adapter? > > thanks > > Barry 68 pin is wide scsi. 16 bit data path vs the 50 pin's 8 bit. Drives might be slightly newer, but check the individual drives. You may also want to look onto 80 pin SCA scsi. These are server drives and the sca adapters are also easy to get.. Generally more robust than the 50 and 68 pin drives. Also hotter, larger capacity , noisier and faster than most 68 and 50. Depending upon how much storage you need, the 73Gb SCA drives seem to be the sweet spot. 10k rpm drives are starting at $20 shipped. You can ignore the tray that is included with many. That is what they used to install them in the server. Just remove the 4 screws and mount it in your Mac. The one thing to be careful of is formatting. Many SCSI drives are not included in Apple's Drive SetUp program. There are hacks to get it to recognize "non-supported" drives. Or a 3rd party drive utility like LaCies will format most any SCSI drive. Len -- You received this message because you are a member of G-Group, a group for those using G3, G4, and G5 desktop Macs - with a particular focus on Power Macs. The list FAQ is at http://lowendmac.com/lists/g-list.shtml and our netiquette guide is at http://www.lowendmac.com/lists/netiquette.shtml To post to this group, send email to g3-5-list@googlegroups.com For more options, visit this group at http://groups.google.com/group/g3-5-list
Re: 68 pin vs. 50 pin SCSI HD?
> One of the 8GB SCSI HD's on my 8600 G3 is failing. Checking around eBay, I > see 68 pin SCSI HD's for sale; and one can purchase an adapter to go to > the mac 50 pin cable. There are many such adapters. Usually from the drive to a 2 x 25 = 50 pin header. > I also noticed that there are many larger size 68 pin scsi HD's around > than the 50 pin - are these 68 pin drives a bit more recent than the 50 > pin ones, and are they usable in my mac with the adapter? The most common large size drive is an SCA type. There are also SCA-to-68 and SCA-to-50 adapters. -- You received this message because you are a member of G-Group, a group for those using G3, G4, and G5 desktop Macs - with a particular focus on Power Macs. The list FAQ is at http://lowendmac.com/lists/g-list.shtml and our netiquette guide is at http://www.lowendmac.com/lists/netiquette.shtml To post to this group, send email to g3-5-list@googlegroups.com For more options, visit this group at http://groups.google.com/group/g3-5-list
68 pin vs. 50 pin SCSI HD?
Hi One of the 8GB SCSI HD's on my 8600 G3 is failing. Checking around eBay, I see 68 pin SCSI HD's for sale; and one can purchase an adapter to go to the mac 50 pin cable. I also noticed that there are many larger size 68 pin scsi HD's around than the 50 pin - are these 68 pin drives a bit more recent than the 50 pin ones, and are they usable in my mac with the adapter? thanks Barry -- You received this message because you are a member of G-Group, a group for those using G3, G4, and G5 desktop Macs - with a particular focus on Power Macs. The list FAQ is at http://lowendmac.com/lists/g-list.shtml and our netiquette guide is at http://www.lowendmac.com/lists/netiquette.shtml To post to this group, send email to g3-5-list@googlegroups.com For more options, visit this group at http://groups.google.com/group/g3-5-list