HDD WD Blue or WD Black - Which Is Best For My Work

1.The WD10EZEX 1TB Blue is a single platter drive and is fast I have one and the WD black is a dual platter is still fast and not a bad drive single platter Higher performance (mainly sustained/average transfer rate) and possibly lower noise and power requirements as it is higher density. Less stuff moving around as there is only one platter. Multiple platter HDD it's more or less scatterd over all the platters, so the disk has to rotate X to get to point Y to read, then back to point X

2.WD1002FAEX has 2 platters, WD1003FZEX has one platter

Why aren't multi platter hard drives faster then single platter ones?

Just think of it like stacked dishes with a space in between. You have a single head reading both platters. The head is like a head on an old LPM record with the old fashioned diamond. Let's call Platter 1 the top one and Platter 2 the bottom one.

First of all, every time the head has to search, it has to start on the outer part of the platter and work its way to the inner part of the platter to search for the data. Further, each platter is divided up into slices called SECTORS. Sectors help the head to know where to search for the data by cutting down the amount of time to search the entire disk. Let's just say there are 16 sectors per platter. And the data is located in a CLUSTER called 1287. The FAT (file allocation table) keeps track of the data at 16,1287. When the computer calls for data, it calls for 16,1287. The disk spins to SECTOR 16, and then starts at the beginning of sector 16 and counts to 1287 and finds the data there.

If the data resides on Platter 2, the head has to skip to the second platter (thus taking time). Then Platter 2 has to spin to lets say Sector 10, Cluster 8395. Same thing repeats. The data is then found there.

So TWO repeats of getting the right sector and cluster are performed. And the head has to jump from Platter 1 to Platter 2 to get all the data.

The computer does NOT store all the data only on one platter or the other in consecutive order. It drops data for storage wherever it is most convenient, wherever the head happens to be when the data arrives for storage. THe head will search for an unused part of the platter to dump the data to to write to the disk. The more full a platter becomes, the more the head must search for parts of the same file. It may not find enough storage on Platter 1 so it will skip to Platter 2 to store the rest of the file.

When files have scattered storage sites it is called fragmentation.

When you delete a file off the hard disk, this frees a bit of space that the head may then store new data on top of. Now you can see why file fragmentation slows a hard disk down. It may have to go to half a dozen "holes" to find all the data for a file to put it together. So the fuller the hard disk, the more data is stored on it, the more files are moved or deleted fromone place to the next, the more fragmented a disk becomes, the more fragmented new files are to stor a bit of it here and a bit there...all over the disk and maybe on both platters.

The more fragmented a file becomes, the chunk sizes of each bit of file increase, and this takes time for the memory and the cpu to put all the pieces back together again like Humpty-Dumpty.

So the more platters you have, the longer it takes to find and put together the bits.

That is why.