What Do Rpm And Cache Of A Hard Drive Mean?

I'm looking to buy a hard drive for an external enclosure that will be connected to my computer using a USB 2.0 port. How important is the RPM and the size of the cache? Specifically, 2 that I'm looking at:

1. 6Tb 5400 RPM Class, SATA 6 Gb/s, 64 MB Cache, 3.5"

2. 6Tb 7200 RPM, SATA 6 Gb/s, 256 MB Cache, 3.5"

Since it'll be connected to my computer using a USB 2.0 port, do the RPM and cache size make a difference?

 

RPM is just pretty much the speed of the drive.If the platter drive spins at 5,400 or 7,200 that is it's rated speed.

I would go with the number two.If you are looking for a faster transfer rate number two is probably a good option.

 

Here is some info on my internal 3ard hard drive to give you a better clue.

WD10JPVX-11JC3T0 ATA Device
Manufacturer Western Digital
Heads 16
Cylinders 121,601
Tracks 31,008,255
Sectors 1,953,520,065
SATA type SATA-II 3.0Gb/s
Device type Fixed
ATA Standard ACS2
Serial Number WD-WXD1E85F4F1H
Firmware Version Number 01.01A01
LBA Size 48-bit LBA
Power On Count 566 times
Power On Time 376.7 days
Speed 5400 RPM
Features S.M.A.R.T., APM, NCQ
Max. Transfer Mode SATA II 3.0Gb/s
Used Transfer Mode SATA II 3.0Gb/s
Interface SATA
Capacity 931 GB
Real size 1,000,204,886,016 bytes
RAID Type None
S.M.A.R.T
Status Good
Temperature 18 °C
Temperature Range OK (less than 50 °C)
S.M.A.R.T attributes
Attribute name Real value Current Worst Threshold Raw Value Status
01 Read Error Rate 0 200 200 51 0000000000 Good
03 Spin-Up Time 5250 ms 115 114 21 0000001482 Good
04 Start/Stop Count 843 100 100 0 000000034B Good
05 Reallocated Sectors Count 0 200 200 140 0000000000 Good
07 Seek Error Rate 0 200 200 0 0000000000 Good
09 Power-On Hours (POH) 376d 16h 88 88 0 0000002350 Good
0A Spin Retry Count 0 100 100 0 0000000000 Good
0B Recalibration Retries 0 100 100 0 0000000000 Good
0C Device Power Cycle Count 566 100 100 0 0000000236 Good
C0 Power-off Retract Count 218 200 200 0 00000000DA Good
C1 Load/Unload Cycle Count 207,728 131 131 0 0000032B70 Good
C2 Temperature 18 °C 129 103 0 0000000012 Good
C4 Reallocation Event Count 0 200 200 0 0000000000 Good
C5 Current Pending Sector Count 0 200 200 0 0000000000 Good
C6 Uncorrectable Sector Count 0 100 253 0 0000000000 Good
C7 UltraDMA CRC Error Count 0 200 200 0 0000000000 Good
C8 Write Error Rate / Multi-Zone Error Rate 0 100 253 0 0000000000 Good
Partition 0
Partition ID Disk #2, Partition #0
Disk Letter G:
File System NTFS
Volume Serial Number 726F38EB
Size 931 GB
Used Space 272 GB (29%)
Free Space 658 GB (71%)

 

Would the second one be faster even though USB 2.0 sort of caps the speed?

 

Use a USB 3.0 port.

 

I agree normally USB 3.0's are marked with a blue or red color usb port.

 

What I'm asking is that even though one SATA hdd might be faster than another, does it really matter if it's connected using a USB port? Doesn't using a USB port cap the speed of a SATA hdd so that spending the money for a faster SATA hdd is wasting that extra money? Or does a faster SATA hdd really run faster than a slower one when connected using a USB port?

 

Data rates for USB ports:
USB 2.0 480 Mbit/s
USB 3.0 5 Gbit/s

Data rates for SATA drives:
SATA I 1.5 Gbit/s
SATA II 3 Gbit/s
SATA III 6 Gbit/s

 

So since my computer only has USB 2.0 external ports (I have a very old computer) buying a faster SATA hard drive and connecting it to the USB 2.0 port wouldn't use the speed that the hard drive is capable of? I'd be saving money by buying the slower one since it can't run as fast as it's made to run because the USB 2.0 port would slow it down anyway?

 

How many computers do you have?

 

Honestly the difference is totally unnoticeable…..looking for extra speed from a mechanical drive is now defunct. Raid is dead as flash evolves.
Your arguing over scraps on the table.

You should entertain the use of flash drives if you want a true difference. ie Solid State!

 

For clarity you are referring to the mobo in your previous thread GA-EP45-DQ6.

Gigabyte specs state that it only supports USB2.0 natively.

So a USB3.0 external enclosure will work with your set up but only at USB2.0 speeds.

As regards the HDDs. 7,200 rpm would in theory be faster but in your case will be bottlenecked / capped by the speed of the USB2.0 port and as such not be any faster than a 5,400 rpm drive. This you stated yourself above.

The only advantage that I can see in getting a 7,200 rpm drive as opposed to a 5,400 one is that if you decide to get a new desktop pc which supports USB3.0 then transfer speed will be higher. If you see what I mean. Guess it all depends on the price difference.

Good Luck

 

This is true in statistics or analytical data, but in practice you will notice sweet FA of a difference from 7.2 tp 5.4 or even USB 2 to 3.
There are simply too many external factors that come into play, which denotes each system as different...…………...What software are you using to determine the difference, which OS, what runs @ startup or in background on your system, how much software is installed and are there any conflictions or defrag issues?
What are the endpoints of the data your transferring?
Do you run networked connections outside your LAN that are different from mine?

Are you hoping for speed transferring data across your LAN or more so the WAN?

etc, etc, etc.

 

As noted above, the RPM (revolutions per minute) is how fast the drive motor spins the "platters" (the actual disks) under the Read/Write head.

While a faster RPM can indicate better disk performance, there are other factors that come into play, including seek times and transfer rates. But while not always true, as a general rule, 7200RPM drives perform better than 5400RPM drives.

But does that matter? For most users, no. For most tasks, including watching movies, 5400RPM drives are plenty fast - at least when there is an ample amount of system RAM.

There are two main advantages to using 5400RPM drives. First, they consume less power and generate less heat. This is why notebooks use 5400RPM drives extensively. The other reason is 5400RPM drives tend to make less noise. So these drives are often used in HTPC (home theater PC) setups where any motor (drive or fan) noise would not be tolerated.

I don't see where anyone answered your cache question. On a drive, the cache (also called "buffer") is a small chunk of fast RAM (or SSD type "flash" memory on "hybrid" hard drives) used to temporarily store data. This is there because reading and especially writing data on a hard drive takes a very long time (relatively speaking) because it is very much a mechanical process.

So that buffer is used by the OS and the drive to temporarily and quickly store data to be written to the drive. This then lets the OS get back to other tasks more quickly.

If all else (in terms of drive specs) is equal, the larger the buffer, the better.

 

I have just one computer. It has USB 2.0 but USB 3.0 is backwards compatible.

I'm not looking for extra speed but the best buy for my money. The faster hard drive costs about $30 more than the slower drive. If my computer can't use the speed of the faster hard drive because I'll be connecting it using a USB 2.0 port, I'd be wasting that $30.

My computer is 9 years old. I have a total of about 24Tb of files on internal hard drives that are backed up on 24Tb of external hard drives. I'm looking into buying a USB 3.0 5-bay magnetic type 3.5 inch hard drive enclosure which can house up to 10Tb per bay. I'm looking at the 6Tb hard drives to fill those bays. If I can save $30 per hard drive, that's $150 total, by buying the slower hard drive because the faster hard drive will never be able to run at the faster speed because it's connected to my computer using a USB 2.0 port, then I want to save that $150. No flash drive is going to give me that much storage space and I don't have enough external ports to add 5 or more flash drives. I need one enclosure with one USB connector that houses multiple hard drives.

Yes.

This is what I wanted someone to confirm that I was thinking.

This is something to think about because I do have to get a new computer.

I don't know what endpoints are. I don't transfer data anywhere. My computer is self-contained. I move/copy files from one hard drive to another at times.

I don't know what a LAN is or what a WAN is.

I don't have a network set up. I have a desktop computer and several external hard drives that no one else has access to. I have cable internet.

None. I'm going by the specs on the website where I'm going to be buying the hard drive. I already have a number of faster and slower hard drives and I don't notice a difference at all when I'm using the files stored on them, whether they're connected to a SATA port on my motherboard or connected with an external USB port. I do notice a speed difference only when I move/copy files from or to a an external hard drive that's connected with a USB port.

I have Windows 10, Windows has determined what runs at startup and I don't mess around with any Windows settings except for things like personalizing my desktop and font size, etc. I have very few programs installed but the ones I use on a daily basis are Media Player Home Cinema, CCleaner, MS Word, Corel Calendar and Notepad. I have a handful of other program installed but I rarely use them, like Winaero Tweaker, Revo Uninstaller, Speccy, WinZip, and Acrobat Reader. I don't do gaming, I don't surf the net, I don't try out new programs offered on line, and I don't download anything from on-line except from reputable places like MajorGeeks, Microsoft, etc. I learned my lesson years ago not to do these things and my computer has been kept safe ever since, no viruses, trojans, etc. Windows scheduled itself to defrag once a week. My OS hard drive only has Windows, programs and My Documents/My Pictures on it.

 

That means the drives will run at USB 2.0 speed - which is less than a third of SATA I data transfer.

I didn't explain cache because I don't believe it'll make a difference when connecting SATA drives to a USB 2.0 port due to the slow data rate.
It's wort mentioning... Consumer HDDs have a cache of 256 MB where as SSDs have up to 4 GB.
But, a SATA SSD connected to a USB 2.0 port will not show the true advantage of SSD over HDD.

 

In most cases for most users, it won't - not when the smallest up there 64Mb - typically considered a large one. I answer just because the question was asked.

 

Thanks, everybody, for clarifying these things for me.