Recommended Posts

Google is your friend and much more can be learned there ; but here is a simple view of things.

First off, in the early days, most hard drives were serially connected through SCSI (Small Computer System Interface) . This was a serial interface where you could connect from one drive through to another and another in a chain.Initially there was a limit of 8 devices on a chain (with the controller itself counting as one ) but it is now commonly 127. Then along came ATA or IDE drives.

The normal 40 pin connectors on your motherboard are PATA or Parallel ATA (Advanced Technology Attachment) connections for IDE (Integrated Device Electronics, meaning the drive itself has a firmware chip which basically contains the drivers and controls needed for using the drive). There are two of these on your motherboard normally, the Primary and the Secondary IDE connectors. Each of these can handle TWO drives . Initially, PATA drives transferred data to and from the processor or RAM at 33MHz, this was increased to 66, 100 and eventually 133MHz. That pretty much pushes it to the limit of the cabling (the jump to 100MHZ and above required replacement of older 40 pin 40 wire cables with new 40pin80 wire cables where every other wire in the cable is a ground to cancel out interference from induced currents caused by the speed at which the data is moving). So with bus speeds on motherboards using multipliers and now being much higher than 133MHz the drive now becomes the true bottleneck of the system.

SCSI drives remained in use in business both for their durability and because of the increased capacity you could obtain through RAID (Redundant Array of Independent{or inexpensive since smaller used to mean cheaper} Disks)

Serial ATA is a kind of fusion of the two. It is the latest developement in IDE and like SCSI it is serial meaning you can connect from one device to another in a chain and have more than two connected to the terminal on the motherboard.

RAID has several forms, but basically speaking it allows you to treat multiple drives as a single drive.

You can send the same data to two or more drives so that it is mirrored; an automatic backup of sorts. If one drive fails , you just replace it and copy the data over from the remaining good one.

You can send one chunk of data to one drive and one to the next so that you can write and read faster. In fact, the limiting factor with hard drives is not so much the bus speed (which represents how fast the data can be read from or written to the built in RAM (cache) on the drive as the actual seek time , the time it takes the head to move from one place to another (max seek time being the time it takes the head to go from one extreme position on the drive to the other) and the actual speed at which it can be read which are both much lower.

Or you can combine the two drives into one larger drive so that you do not run out of space (originally the most common use since early drives were very small by todays standards. Once Bill Gates thought there would never be a need for drives any larger than 504MB, he later relented and thought that 2GB drives would serve adequately for eternity. Then they jumped to 137GB as the largest we would ever need. Now even that is far surpassed).

So SATA allows faster transfer over the bus to the drive(s) involved than PATA does, and RAID allows you to combine more than one drive into a single virtual drive.

Do you need these? Well there is the big question. Whether it is necessary or worth the money .

Most people have gotten along fine for years with a single PATA hard drive and cdrom.

Yes, there are some instances where it is useful to have the secure knowledge that everything is being automatically backed up or some cases where the faster loading time is worth the extra money; and hard drives have been growing in size and speed and dropping in price . Motherboards are increasingly including SATA built in and high end PATA boards have for years had RAID connections (where you had four PATA connectors instead of two and could enable raid to use the second set in one of the allowed configurations).

Link to post
Share on other sites

TY Pete,

now why would i want to use google, then you wouldn't of had the enjoyment of answering someones question :)

and the fact that i dont know how to use google....

and why have a forum if everyone just says "GOOGLE IS UR FRIEND!"

Thanks :)

much appreciated

Link to post
Share on other sites
TY Pete,

now why would i want to use google, then you wouldn't of had the enjoyment of answering someones question :)

and the fact that i dont know how to use google....

and why have a forum if everyone just says "GOOGLE IS UR FRIEND!"

Thanks :)

much appreciated

Why would you want to use Google? The same reason why we do. To find answers that we may not have in the top of our head. I guess we do the hard work and you reap the benefits...lol Some of the answers to questions on Google will put you to a Message Board Forum like this one or others.

Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...