CPU limited by HDD? What does this mean?

crystalklear64

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I was browsing the CPU threads and saw this:


What does that last sentence mean? Is the HDD a limiter to the CPU in some way?

Thanks.
 

Evilonigiri

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The slowest component in any pc is the HD.

For example, when opening a program, every component, like the cpu, must wait for the HD to spin up and load the program. It usually takes awhile for the HD to spin up and find the program.
 

crystalklear64

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So.. am I understanding it correctly that theres no point in having a CPU faster than your HDD? And if so, how do you compare CPU speed to HDD speed?
 

dariushro

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A fast HDD improves loading and unloading times significantly , your pc feels much more responsive , ofc you'll need a good cpu too for that to happen.

After the program is loaded , it's pretty much up to cpu/gpu/ram.
 

Evilonigiri

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Well that's only in stuff like opening programs or browsing web and simple stuff. When it comes to encoding, video editing, and other intensive programs, a power cpu is needed. I'm not a very knowledgeable about these things but the data is stored into the cpu cache and ram. The cache and ram can store data also, however it transmit data at a much higher speed, therefore the cpu doesn't have to wait for them to respond.

Another example is games. All the data is stored into the ram, after the HD loads it. Then the speed of the cpu isn't limited. However if the game takes up more ram than what you have, then the HD has a paging file size that allows it to act like ram, but at a much slower speed. That's why ram is important.
 

Vokofpolisiekar

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The CPU will always be faster, so there's no way you can draw a line between owning a cpu thats equal to the HDD in speed.It's something you can't avoid. If you want to come close, SATA2 with NCQ (debatable in real efficiency) is the fastest economical way. Then comes raid etc.
 

Grimmy

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Actually the floppy drive is the slowest. :lol:

Then the CD/DVD drive

Then perhaps USB devices flash/external HD

Then the HD.

The trick to remember, everything that is ran on your PC, is executed in memory or RAM (perhaps the fastest component).

Here's an article on flash drives with movies:

TG Video: Fusion io - the power of 1000 hard drives in the palm of your hand

Been awhile since I saw the movies.. but note how long it takes the copy data the size of DVD on that particular drive.

Edit:

Also note how much that costs.. :lol:
 

evilshuriken

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I think people need to stop doing this.
The SATA2(or even the first) interface is not truly pushed by any consumer level HDD that I know of. You need to be careful with what you say, many newer pc users might not understand that the interface a HDD uses will not determine it's performance.
An UltraATA interface would bottleneck newer harddrives, but not as much as you might think. I get what you mean with NCQ, but please keep the interface out of these discussions.

Also, there is no way a HDD can come close to a cpu's performance, in any configuration. It's a bottleneck we will live with until SSD technology takes over and performance starts to catch up.
 

Vokofpolisiekar

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Doing what? Naming the means of which it is sold by? If I went on the subset of SATA(1) ref 2 that will confuse more. Buying today, you are bound to buy a serial ata HDD which is named SATA2 wrongly.

Most HDD's sold today are at the level of 7200rpm and 8mb buffer, so it's logical that I'd name an interface sans deeper spec. The world revolves around the latest offerings, and if Timmy buys a mobo with 8 SATA2 ports then he'd be inclined to buy a SATA2 HDD enventually. By stating "..SATA2 with NCQ is the fastest economical way" I'm actually referring to what your avg bloke on the street would buy without doing research or having a clue as to what it entails.

So, the interface was addressed wrongly, but the industry thrives on the naming and sells by it. I made mention of the connecting interface, not the tech behind it

(no offense meant by this post, just my view)
 

jsc

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Unless you want to go through the hassle of making a USB flash drive bootable, flashing a BIOS comes to mind.
 

Grimmy

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That's beside the point I was making. The floppy is a media storage, such as a HD. So its the slowest by far. :kaola:
 

Vokofpolisiekar

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True, I've yet to try the USB way. But my XP is streamlined well enough and with Vista it becomes obsolete.

Btw, I wonder how many people actually do install AHCI drivers for sata drives? I just did it because NCQ requires it and well... I just didn't like seeing IDE on my drive in Windows... :kaola:
 




I'll use an old, old example that may help put this stuff in context:

Your Hard Drive and Optical drives act like a filing cabinet - That's where stuff lives that you aren't working on at the moment. If you need that stuff, you have to go get it and put it on your desk before you can do anything.

Your RAM (Memory) is like the space on your desk. If it's already on your desk you can work on it immediately, yah?

The CPU is the one actually doing the work.


OK - When you're opening a program, or doing something completely new (like transitioning to a different area in a game) your computer has to go get the new information from the Drive(s) and put it into memory before your CPU can do anything. As pointed out above: In this particular instance, the system has to slow down to the speed of the Drive - Information has to hit memory before your CPU can do the work. During this period of time, the advantage of having a faster CPU is nullified by the (relatively) slower drives, yah? Because even if the CPU were slower, it's still faster than the Drive can provide information to work on.

This situation is the reason some gamers will spend big bucks on a RAID array of small, fast hard drives: Faster seek and transfer rates mean the data hits memory faster and the CPU can get to work sooner. Think about that in a gaming situation: If your computer can load and render the area before the other guys' can you may gain a couple seconds where you can kill him while he's still loading the game. Free Frags!! And if you want, sometimes you can camp and really piss off the people around you by getting them into a cycle where you kill them, they reload, and you kill them again while their computer is reloading again, etc etc etc....

BUT!!!!

The above situation only occurs once in a while. Most of the time the game/program/whatever is already loaded into active memory. So most of the time your faster CPU isn't limited by Hard Drive I/O ('Input/Output') So, except during the limited times your comp has to get data from the drives, your faster CPU is free to work. And since your faster processor is free to be... well... faster for the great majority of the time, then it's still better to have a faster one than a slower one.


Hope that helps, anyways...




- Also, this is why old school single player guys (like me) don't bother with RAID arrays on our home PC's because (in my case) I get to take an extra swig from my coffee cup while the computer is working. ;)
 

evilshuriken

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Vokofpolisiekar, your post sort of made it sound like the interface was the determining factor of performance.
I know now that is not what you meant by it, and I agree with what you say. I am not recommending that anyone go out and buy an ata HDD. There are other advantages of newer interfaces other than performance, like those lovely and tiny Sata cables. :lol:

Also, why would I take offense to perfectly reasonable discussion? :heink:
 

jimmysmitty

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Don't forget no more master/slave BS or jumpers on the back of the drives. Just plug in and play. I love SATA and especially when I RAID0 it. The speed increase oce UATA and even one SATA drive is nice. I like watching programs load like nothing and being able to drag and drop a 4GB file from point a to point b on the HD.

Als most HDs now are fixing into the 16MB cache area and 32MB is more enthusiasts. Although I am not too sure that it will change much but hey the more cache the merrier.
 

cnumartyr

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Only thing to remember on some HDDs is the 1.5 GB/s limiting jumper.

My Seagates had it and improved performance when I realized it and removed it (about a 25% read increase with HD Tach).

2 of them in RAID0.
 

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