RPMs (5900 vs 7200)

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JOSHSKORN

Limp Gawd
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What's the difference between a HDD with 5900 RPMs vs 7200 RPMs? Basically, my question is this. I've read somewhere that based n your connection interface, whether it's USB 2.0/3.0, SATA II/III, you may not be able to notice a difference in performance. Is such information accurate? I'm looking to get a fast USB 3.0 HDD. For the size that's out that I want (8TBs), I only see 5900 RPMs, not 7200 RPM drives...yet. Advice?
 
>What's the difference between a HDD with 5900 RPMs vs 7200 RPMs?
From a performance perspective it's access times, as the faster rotating drive has lower average rotational delay. Downsides are typically more noise, power consumption and heat.

>I've read somewhere that based n your connection interface, whether it's USB 2.0/3.0, SATA II/III, you may not be able to notice a difference in performance.
The interface versions differ in bandwidth. Since access times are orthogonal to that, depending on your use case you might still see a difference in performance between 5900 and 7200rpm drives even when connected via crappy USB2.0.
 
It makes sense to have the OS on an SSD, my assumption is that you are using the drive for another purpose.

It depends on how each drive is made.
If they have the same platters and data density, there is a proportional difference in transfer speed.
Also the seek time of the faster spinning drive will be slightly less.

A straight forward metric wont work because some slower spinning drives have a high data density so data transfer rates can be the same or even higher.
(to put it another way, some faster spinning drives dont have the highest data density, you need to verify the performance of each drive)
If you transfer large files all the time or dont care for the few mS before they start transferring you wont care about the seek time.

I use an SSD for my OS and fast transferring drives for data, these can be 5900 or 7200rpm.
I dont care, as long as they on the higher end of the DTR range.
 
Just make sure its got 1TB platters as I think thats currently the highest density around.

I have a couple of 5900rpm HDDs that I have in NAS boxes.

To be honest HDD speed is largely not worth worrying about nowadays. Whatever you buy...will be sloooow.
 
If it spins, it's mass storage only, and for that it functions fine almost regardless of the spin speed.

Areal density is so high on modern drives that even 5900 rpm drives have sequential rates near 150MB/sec.
 
Drives with higher RPM take less time to start reading/writing data. It's measured in ms, and is an unnoticeable difference to most folk. For example, a 4TB 5900RPM drive will have a latency of 5.16ms, while a 7200RPM drive would have a latency of 4.20 ms. Can you notice a 1/1000th of a second difference? An SSD has a latency of generally 0.1ms or less, which is why they're the most frequently recommended OS drive.

Also, a pet peeve of mine: RPM is already plural. (Revolutions Per Minute) No need to add an "s" to the end.
 
The difference is noticeable in many but not all use cases. However it is not as big a difference as it used to be. Modern 5400/5900 RPM drives are a lot better than they used to be. Back in the early 2000s I would tell just about anyone to avoid 5400RPM.
 
TeeJayHoward said:
Drives with higher RPM take less time to start reading/writing data. It's measured in ms, and is an unnoticeable difference to most folk. For example, a 4TB 5900RPM drive will have a latency of 5.16ms, while a 7200RPM drive would have a latency of 4.20 ms. Can you notice a 1/1000th of a second difference? An SSD has a latency of generally 0.1ms or less, which is why they're the most frequently recommended OS drive.

Also, a pet peeve of mine: RPM is already plural. (Revolutions Per Minute) No need to add an "s" to the end.
Click to expand...

Lets just say you're writing 100 GBs of data to a hard drive, or even accessing that much data from a hard drive. What does that translate to how much time it would take to write that amount of data on a drive running at 5900 RPMs vs 7200 RPMs? And again, would such thing as an interface (for example: eSATA, USB 2.0/3.0, SATA II/III, or a wired gigabit connection to a router with a connected USB 3.0 HDD) bottleneck the performance at 7200 RPMs vs 5900 RPMs? You claim that the difference between 5900 and 7200 RPMs is virtually unnoticeable, but until what point?
 
It depends on the actual drives.
Look at the data transfer rates of the drives you are looking at.
Its already been explained above.
 
dandragonrage said:
The difference is noticeable in many but not all use cases. However it is not as big a difference as it used to be. Modern 5400/5900 RPM drives are a lot better than they used to be. Back in the early 2000s I would tell just about anyone to avoid 5400RPM.
Click to expand...
7200 RPM drives have improved by the same amount in the same time, haven't they?

JOSHSKORN said:
Lets just say you're writing 100 GBs of data to a hard drive, or even accessing that much data from a hard drive. What does that translate to how much time it would take to write that amount of data on a drive running at 5900 RPMs vs 7200 RPMs?
Click to expand...
It depends on the workload. If you're doing a sequential transfer, you're going to find the higher RPM drive to be approximately 72/59 == 22% faster.

While TeeJayHoward's assertion that a single seek is about 1/1000th of a second faster, you have to think about how many times you want to do a single seek. If your workload is random, then you'll do many seeks -- and before you know it, 1/1000th of a second becomes whole seconds.
 
JOSHSKORN said:
Lets just say you're writing 100 GBs of data to a hard drive, or even accessing that much data from a hard drive. What does that translate to how much time it would take to write that amount of data on a drive running at 5900 RPMs vs 7200 RPMs? And again, would such thing as an interface (for example: eSATA, USB 2.0/3.0, SATA II/III, or a wired gigabit connection to a router with a connected USB 3.0 HDD) bottleneck the performance at 7200 RPMs vs 5900 RPMs? You claim that the difference between 5900 and 7200 RPMs is virtually unnoticeable, but until what point?
Click to expand...

It wouldn't matter how long cos any sane person would find something else worthwhile to do while it copied and come back to it later.:D

Really they would.
 
mikeblas said:
While TeeJayHoward's assertion that a single seek is about 1/1000th of a second faster, you have to think about how many times you want to do a single seek. If your workload is random, then you'll do many seeks -- and before you know it, 1/1000th of a second becomes whole seconds.
Click to expand...
Yup, and that's the deal. For an OS drive where you're doing lots of random seeks, you'd want a fast drive. Loading a couple hundred small textures into memory for the game you're starting up? Fast drive. If you're storing movie files? The 5900RPM drive works just as well as the 7200RPM drive.

JOSHSKORN said:
Lets just say you're writing 100 GBs of data to a hard drive, or even accessing that much data from a hard drive. What does that translate to how much time it would take to write that amount of data on a drive running at 5900 RPMs vs 7200 RPMs? And again, would such thing as an interface (for example: eSATA, USB 2.0/3.0, SATA II/III, or a wired gigabit connection to a router with a connected USB 3.0 HDD) bottleneck the performance at 7200 RPMs vs 5900 RPMs? You claim that the difference between 5900 and 7200 RPMs is virtually unnoticeable, but until what point?
Click to expand...
For large sequential transfers like that, RPM is a secondary or even tertiary characteristic. You could have a 5900RPM drive that transfers files at 150MB/s, and a 7200RPM drive that caps out at 130MB/s, although it's likely the other way around. Disk platter density is more important than RPM in this situation. This is one of the few scenarios where it's okay to look at the numbers the manufacturers advertise, and compare them directly.

The interface shouldn't slow down a 5900RPM drive over a 7200RPM drive. If the drive can move data at 200MB/s, and the interface can move data at 200MB/s, you should get 200MB/s, regardless of spindle speed.

daglesj said:
It wouldn't matter how long cos any sane person would find something else worthwhile to do while it copied and come back to it later.:D
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I don't get it, it's just 100GB. Copying that small amount of data should only take seconds, right? :D
 
TeeJayHoward said:
Y

I don't get it, it's just 100GB. Copying that small amount of data should only take seconds, right? :D
Click to expand...


No this is a torture run of 100GB of small JPEG files and their thumbnails being copied to the slow end of the nearly full HDD

Mwuhahahaaaaaaaa:D
 
What 8TB drive are we talking about ? If it's a Seagate Archive, are you aware of SMR ?
 
7200/5900 -> 22% faster rotational speed. Is that really enough to notice? WD said that overall performance depends about equally on RPM, sustained sequential data transfer rate, and random data transfer rate, meaning RPM matters roughly half as much as that. Is that really small enough to notice? SATA III vs SATA II won't matter for hard drives, even 7200RPM, unlike USB 2 vs. USB 3.
 
WD sells Red drives for consumer NAS applications, and Red Pro drives for business oriented NAS applications (without going into enterprise drive territory). The former is 5K and the later 7K rpm, what can we conclude ?
 
larrymoencurly said:
7200/5900 -> 22% faster rotational speed. Is that really enough to notice? WD said that overall performance depends about equally on RPM, sustained sequential data transfer rate, and random data transfer rate, meaning RPM matters roughly half as much as that. Is that really small enough to notice? SATA III vs SATA II won't matter for hard drives, even 7200RPM, unlike USB 2 vs. USB 3.
Click to expand...

As mentioned above - the rotational speed affects the access, or seek, time, measured in milliseconds for most hard drives. A difference of 1ms per seek would be inconseqential on a single file seek. But that hit happens every time you access a different non-contiguous file, or a file is fragmented and has to jump areas on the platters. Last time I looked, Windows has hundreds, if not thousands, of seperate files that it accesses when it boots up. Games and most buisness applications are typically similarly complicated.

So take that 1ms difference, and multiply it by hundreds, or thousands, and that's where you will notice it.

SSDs are faster because of their ~much~ faster access times. And that's why you really notice SSD speed, because the access time is faster.

If your just using the drive for bulk storage, then yeah, storage capacity trumps access speed. But if you are trying to use it for work, 22% speed difference is noticable, but it pales next to the 200-500% (or whatever number it ends up being, I didn't do the math, but it's orders of magnitude difference) speed difference between any of those and an SSD.
 
Brian_B said:
If your just using the drive for bulk storage, then yeah, storage capacity trumps access speed. But if you are trying to use it for work, 22% speed difference is noticable, but it pales next to the 200-500% (or whatever number it ends up being, I didn't do the math, but it's orders of magnitude difference) speed difference between any of those and an SSD.
Click to expand...

Basically, I have more or less an HTPC. I'm going to be adding a storage drive to it, that is 8TB. This will be used to access HD TV content as well as other videos or pictures I'd like to upload. I own an InfiniTV6 ETH. If you're unfamiliar, basically you put a CableCard into this device, and you end up with 6 TV tuners. Ideally, this computer's hard drive will be accessed locally, as well as by 2 other computers (which serve as "extenders") on the network to view HDTV.

That said, all 3 computers could be accessing this hard drive at one time, whether it's for viewing HD TV, recording, moving/saving/deleting other content, all simultaneously. It sounds to me like a 22% gain seems justified. Am I right about that?
 
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