Quick HD question from a computer idiot...

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AlexHerd

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Hey all, so Im looking at a new HD for my laptop, and the only difference between the two that Im looking at is the cache size. One is 16mb the other is 8mb. Does the cache size of the HD have any affect on recording? I've heard it doesn't, but I just wanted to check before I purchased. Thanks!
 
The large cache size makes read write operations from drive to board appear faster when large file transfers are taking place. For you it wont make much difference. here is why :-

A cache works by reading a block of information from the drive surface to a very fast but small piece of ram ( known as cache ram ) .

When your cpu wants the information from the drive it asks for "data" from "drivecluster" , the cache reads this plus all of the contigeous data that is surrounding that cluster so that the chances are that when the next call to read data from the drive comes , it will already be in cache as most read operations from anykind of storage tend to be stored contigeously ( next to the last read address ). this means the drive will not actually have to access the platter , but gets it from the cache memory giving the effect of speeding up drive read/write functions .

The platter assembly is mechanical , hence it is very slow to respond compared to the cache which is a solid state chip and has no moving parts.

The cache also stores information that has been processed back to the platter in it's own time, this means the cpu is freed up to do other tasks and doesnt have to wait for the data to be written to the platter ( which is very slow as it is a mechanism rather than solid state).

small file transfers do not really benefit from this as the files to to be scattered all over the available drive platter so the chance of getting a "cache hit" when a piece of data is requested is much smaller because the small files are not stored contigeously on the hard drive surface.

This is why drive performance suffers so badley when you have large file fragmentation , and when you defragment a hard drive you rearrange the file system so that everything once again becomes contigeous and the cache can work at maximum efficiency!

;)
 
Actually rotation speed pays a much more important role in performance , the 10,000 weston digital raptor hard drive blows away most other drives on the market right now in all areas until you step up to the faster 15,000 rpm ultrascsi 320 server drives. 7200 rpm hard drives are noticably slower than the raptor .

Notebook hard drives have slower spin speeds (typically 3200rpm or 5400rpm) to save power and prolong battery life. If you are buying a hdd for a laptop look for the largest capacity over any other spec as a laptop is not really intended to be a performance machine anyway ( there are exceptions if you have the cash though ) ;)
 
No, replacing the one I currently have.

Thanks for the help everybody!
 
for recording and laptop drives? NO... as long as it's 7200RPM it's fine...
 
Could I get away with 5400? I have a 5400 in here currently which runs pretty darn hot most of the time. Would stepping up to a 7200 be a bad idea? Any feedback would be great. Thanks for all your time so far!
 
5400 is fine , 7200 wil run even hotter and they are still not that common in notebooks .
 
cortexx said:
5400 is fine , 7200 wil run even hotter and they are still not that common in notebooks .

5400RPM drive are are actually quite slow, and notebooks have moved to 7200RPM recently... um the only thing i can suggest is to have one of those padded thing with fans placed under the laptop. that pretty much will solve any heat problem
 
If a laptop comes witha 7200 rpm drive it will be designed to cool it peoperly , if its an older laptop you cannot put a 7200 in place of a 5400 because it gets substantially hotter and the notebook will not be able to dissipate it. The external cooling trays for them only make a marginal difference and certainly will not provide the 7200 with adequate cooling, they are more a gimmick than anything else.

I see this alot in our service department , tons of laptops fail when faster hdd are installed and they then over heat.
 
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