my desktop hdd vs laptop

will a desktop 7200RPM 2MB buffer hdd be faster than a 5400RPM 8MB laptop hdd? because if i get a laptop with the 5400 i dont want to lose speed

 

A 7200 RPM drive will be faster then a 5400 rpm drive.

 

wrong the buffer will load 4 times more data the desktop hdd whereas a 7200rpm drive is only 25% faster. The difference wont be super huge but the laptop hdd will be faster.

 

The desktop drive will still be faster because of the faster rotational speed. Cache is important too but a faster rotational speed is preferable, as it will enable quicker access and transfer to your files. As an example, recent desktop hard drives running at 7200 rpm are beginning to come out with 16 MB of cache built in. Even with double the typical cache, these drives don't even come close to the last generation 10,000 rpm Raptor drives made by Western Digital, which have only 8 MB of cache. If you want the similar speed, you can always buy a 7200 rpm notebook hard drive off an online retailer later on.

 

RPM's is the biggest factor for HD Speed. I buy drives with at least 7200 rpm, the speed of you computer is only limited by its slowest peice of hardware.

 

if i bought the HP laptop with the lowhest hdd i can just use any standard 2.5" notebook drive right? I think newegg has lke 100GB one for like 140 i guess finding a 120GB 7200RPM is hard to find too? and when i get the hdd i can jsut put it in, then install winxp home edition with my backup cd then get all the drivers from my computer from the hp website then burn it to a dvd/cd then install them on my laptop right?

 

How about running an HDTune benchmark test? Then printscreen the results, save the picture and post it here. Someone could do the same with a 5400RPM, 8MB cache laptop drive.
http://www.hdtune.com/

 

The cache doesn't have such a big effect. The RPM increase gives you a 33% improvement on everything (most importantly seek time)

The cache just helps you if you're repeatedly accessing *the same* 8 MB. Sure, it's helpful, but it's *nothing* compared to the RPM increase.

 

My desktop pc with a seagate 7200RPM 2MB buffer desktop pc with a Celeron D 2.4ghz/ Dell pc

Transfer Rate:
Min: 1.2mb/s

Max: 55.8mb/s

Average: 40.9mb/s

Access Time: 15.8ms

Burst Rate: 74.6mb/s

cpu usage: 13.6%



seems pretty crappy i dont know if i should go with the 120GB 5400RPM or the 100GB 7200RPM ;/

 

How'd you test that?

The CPU usage seems suspiciously high (Although a 2.4GHz Celeron isn't exactly "fast"). Might want to check if your HD is set to DMA mode instead of PIO.

The burst rate seems ok though, and the max transfer rate might not be wrong either. Might have been a few MB higher, but doesn't look terrible. The access time looks high though.

I'd guess it's because your HD is set to PIO mode instead of DMA. That would explain the high cpu usage as well as the odd numbers.

A 5400 RPM drive would *not* be faster though. With that, you'd be lucky to reach 50MB/S burst rate

 

so with the 7200RPM 8mb buffer i would notice faster bootups and applications would load up quicker? thats about it? i mean is it worth it? how do i change it to DMA mode and whats the difference?

 

The most accurate way to put it would be to say that everything that uses the HD would be faster. Bootup and loading applications are the most obvious examples of this (And most other access is due to a lack of RAM, and so the answer to that is to buy more RAM, rather than a faster HD), but yeah. Check the HD light for activity when you're working/playing games/whatever. If the light is hardly ever on, a faster HD won't make a difference. If the disk is frequently used, the faster HD will be very noticeable.

About DMA/PIO:
Open the device manager (right click on my computer->properties->hardware)
Under IDE ATA/ATAPI controllers, you should see a couple of IDE channels. Right click on each of them, open their properties, and under advanced settings you can see which device (if any) is connected to this channel, and the mode it's running in. Then just make sure to set it to "DMA if available". And if you can't do that for some reason, it's time for some serious troubleshooting.

The difference is basically that PIO sucks.
PIO (Programmed Input/Output) means that the CPU has to handle every single transfer. That is, the CPU sends a command to the HD to initiate reading a block. Then it asks the HD whether it's finished yet, and if it isn't... The CPU asks again.
Sooner or later, the HD operation will finish, and the CPU gets the one block back. Then it stores that to RAM, and repeats with the next block.
It's sloooow, and it hogs the CPU something awful.

DMA (Direct Memory Access, I think) means that the memory controller handles the transfer. Basically, the CPU sends a command to start transferring x bytes from HD to an area in RAM. Then the memory controller and HD controller handles things from there, read data from the HD, dumps it into RAM, and when the entire transfer (which can be pretty much any size) is done, the CPU is notified. It's more efficient because it doesn't involve the CPU (Which might be busy with other stuff), and it lets the CPU work on other threads while the transfer is in progress.

 

Go with the 7200 rpm drive because you can always get an external case for your original drive and use it as additional storage space.

 

Nowaday, all the HDs are 7200rpm seem to be hard to find out a 5400rpm for desktop HD, but still easy for laptop HD. Whatever SATA or EIDE, they also support 7200rpm with 8MB or 16MB. 10,000rpm not many people need this becasue of high price.

 

I thought this was just a measure of speed. If your shopping for a desktop hdd alwasy got 16mb cache and at least 7200rpm.