Aldi External HDD €179.99

therecklessone

It looks hideous, but appears to be a bargain.

http://www.aldi-stores.co.uk/ie/specials_01_11/external_hard_disk.html

160GB for €179.99.

Woden

nice price on it alright, what are the performance of these external hdd's like?

^whitey^

Is it really a bargin considering it only as a 2mb cache?

How does the cache affect the performance on a hard disk anyway?

Woden

well not sure of the main function but i heard the cache is useful for save games and the like which can be stored in it and then quickly loaded, i presume instead of accesssing the main hard drive?

po0k

It's used as part of the access electronics for the drive, in association with the firmware it's used for optimising access for best perfocmance, burst read and write etc.
Whatever is stored in it is completely transparent to the host device.
It's used as a buffer between the main machine and the actual disk platters so that the host devie doesn't need to worry about waiting for the data to be actually written the the platters.
The electronics takes care of it.

BigEejit

Depending on manufacturer and firmware level it is sometimes used to prefetch and predictive fetch ... prefetch means that it will get the sectors that the OS asked for and also the next 20 (or whatever number) sectors off the disk and store them in cache and (hopefully) the OS will look for them (after it has finished processing the last sectors) and they will be presented immediately ... predictive fetch is where it will fetch regularly accessed sectors when nothing else is happening