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m-kong
10-30-2002, 04:18 PM
G'days again,
80Gb 7200rpm Westerndigital 800JB 8Mb whats so great about the JB 8mb thingo :D
What is the difference in this mb thing
eg in WD drives
BB= 2mb JB= 8mb EB=0mb

Obviously the 8mb is better but can someone please explain the great advantage of this mb writer or what it is actually called, as i dont know. :D

Also would anyone know if Seagate have this mb write system in their drives. Ie do they sell 0mb 2mb and 8mb speeds of writing.

Thankyou

I need help as i am still assuming that the mb rate is the writing speed or something similar to that, someone correct me please :D



Also what is the advantage of the ATA speeds ie 100 and 133.

Darthtanion
10-30-2002, 11:16 PM
In a general sense, the larger cache improves the speed at which your hard drive writes data. To give you a little better idea, here is a copy/paste from whatis.com (http://www.whatis.com).

A disk cache is a mechanism for improving the time it takes to read from or write to a hard disk. Today, the disk cache is usually included as part of the hard disk. A disk cache can also be a specified portion of random access memory (RAM). The disk cache holds data that has recently been read and, in some cases, adjacent data areas that are likely to be accessed next. Write caching is also provided with some disk caches.

And in answer to your question, I don't believe that Seagate has the larger 8MB cache available on thier line of hard drives. This is only being seen in the Western Digital brands, but with the success of this technology, it probably won't be too much longer before we seeing it becoming more widespread throughout many of the hard drive brands.

Mr. C
10-31-2002, 12:34 AM
The computer simply accesses data through RAM much faster than it can through the process of seek & read through a hard disk. That means the potential for faster data flow exists when you have more cache to hold data. Of course you only see actual benefit when you are accessing information which currently resides in the cache.

For larger files such as programs, .mpg, etc. there should be an improvement in transfer time. For smaller files there is little if any difference noticable as the information flowing can be direct enough to not require a lot of use for read-ahead.

As to the issue of ATA 100 vs 133.
A significant difference in benchmark scores hasn't really been acheived by 133 in real world testing. Not enough to make it worth spending additional money on for sure.
Better in my opinion to go with ATA 100 and set aside the money saved for incorporation of Serial ATA as it looks quite promising for boosting performance in the future.

Wiggo
10-31-2002, 07:37 AM
Really it's only because of the WD JB series that the ATA66 standard is made redundant as before these other ATA100 hard drives could not use all the bandwidth offered by ATA66. The cache on the JB's is the main reason that the ATA66 standard is no good for this drive.

Quite frankly the ATA133 standard is a farce, the ATA66 standard has just been put to sleep and nothing yet is even getting to pushing ATA100 to it's limits (if you want better speeds than that wait for Serial ATA II).

So unless your going to use a RAID array ATA133 ain't worth it IMO. : peace2:
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