View Full Version : Noticable speed bump going from 5400 HD to 7200?

05-18-2005, 06:26 PM
I'm servicing a 400mhz G4 Tower and it occurred to me while listening to the VERY noisy IBM 5400rpm HD whirring away that a bigger, faster HD would be good. My question is how much of a speed bump would I experience with that? I only ask because I seem to really notice the lag when accessing the drive.

05-18-2005, 08:46 PM
Generally, I'd say make sure you've got plenty of RAM, then worry about the drive.

If you've got enough RAM, your disk access should be infrequent, so the faster drive won't be as big a boost as if you have only 256mb or even 512mb.

If you're doing a lot of work that requires frequent disk (database, Photoshop, iMovie, iPhoto, iTunes, etc.) access however, the drive performance increase will be noticeable no matter how much RAM you have.

05-18-2005, 08:53 PM
non-scientific: 4200 -> 7200 ... huge improvement! (internal 4200 vs. firewire 7200)

05-18-2005, 09:22 PM
Yes, you will notice a difference. It's there if you watch for it.

05-18-2005, 09:24 PM
Another unscientific guess - Maybe that 'very noisy' hard drive is not accessing various parts of the drive as easily as it used to, and replacing with a newer drive will result in faster response for some functions (like booting significantly quicker), with the bonus of working with much less commotion, making the computer more pleasant to use... :)

05-18-2005, 11:43 PM
All great comments, thanks ppl.
I should have been more specific: the machine does only have 512mb (I can't believe we're already up to saying "only" 512mb!), but I am noticing the disk access a helluva lot more than on my g4 700mhz with 640mb. Yes, I'm probably at a sweet-spot kinda place with that extra 120-odd meg making a difference to swap-access, but anyway...maybe I'll try to persuade him to upgrade.

Any other (cheap) speed thoughts gratefully accepted!

05-19-2005, 12:22 AM
If you tend to keep lots of apps running, or if you use Classic, then I think adding another 512mb or even just 256mb will give you a nice increase in speed. Of course, a new hard drive will give you more room as well as more speed, so it's really a judgement call. Getting both RAM and a new drive would be nice, but so would getting a G5! ;)

05-19-2005, 07:39 PM
In my opinion, the spindle speed of a hard drive is a trivial statistic. It has some small effect, but very little overall.

The fact is, newer hard drives are faster than older hard drives. This is the most important speed factor. The most expensive 7200 rpm hard drive from 1995 might transfer data at around 4.5 or 5 MB/s. A 5400 rpm hard drive from today might transfer data at 45-50 MB/s, a factor of 10 times faster. This should be a clear indicator that the spindle speed doesn't count for very much. The 'newness' of a drive is by far the biggest indicator of its speed.

So, many people buy a new drive with a faster spindle speed than their old drive, then interpret the spindle speed as the important indicator of speed, when it is really the fact that the new drive is from a later technological generation, in some cases a MUCH later technological generation.

Next, the electronics makes a difference. Some companies, such as IBM/Hitachi, tend to make faster electronics than say, Maxtor (in general). 3.5" drives have faster electronics than 2.5" drives. Higher priced premium lines from a company have faster electronics than the cheap low-end lines from the same company.

Finally, the spindle speed make a difference when all other factors are equal. If you compare two 3.5" ATA/133 drives from IBM/Hitachi for example, the 7200 rpm drive will be faster than the 5400 rpm drive.

Faster electronics do tend to coincide with faster spindle speeds since every little bit of extra speed matter on high end drives, whereas in the low end drives price is the prime motivator.

If you see speed tests of hard drives, it is typical for the higher spindle speed drives to be faster than the lower spindle speed drives, both for reasons of the actual spindle speeds and the electronics used. But if you compare 'generations' of hard drives, you will soon see that this is by far the biggest indicator.


05-20-2005, 01:01 AM
Wow, great post Trevor, I really appreciate it. Maybe that's why I think I notice the disk access lag between two G4's only 350mhz apart in chip speed. The old G4 tower at 300mhz versus the eMac at 700mhz, similar RAM amounts, but the eMac seems to be much faster at disk access than the tower. mmm...could be time.