specifications - Is there some seller that sells Hard Drives with Gibibyte capacity?

I read somewhere that smaller (in terms of disk space) hard drives are faster than equivalent but bigger hard drives. How true is this? In other words, say I have two hard drives. Both are of the exact same brand and specs, but one is an 80GB while the other is 500GB. Which would be faster? Or does storage capacity not have any effect on speed at all?

A generalisation isn't useful, but mostly when talking similar models/same series I'd say the larger drive would be faster due to higher data density in some way (be it more platters and heads, or just denser platters).

The bigger model would likely be newer as well and could benefit from firmware and other production improvements.

Size is but one of numerous considerations in determining the actual realized performance of a drive.

Rotational speed is one of the factors that determines the write rate. A 15k RPM drive would likely be faster than a 10K RPM drive of the same specs and size. (Assuming all things are equal which they are not in most cases)

The next thing to consider is the expediency in which the voice coil can move the read/write heads for a seek or continued file access. The latency introduced by the moving voice coil read/write head is perhaps the most significant source of delays in the read/write process.

The electronic controller board and what connectivity BUS it supports is also another significant determination of speed. A good example is the various versions of SCSI disks which supported higher and higher speeds with every revision to the scsi standard. SAS drives offer aditional performance over SCSI,IDE and SATA because of increased BUS bandwidth.

The number of platters is indeed also a factor but not the most critical performance consideration.

You can not. Drive speed depends on lot of things, mostly on disk data density (is rotational speed is equal).

If you can, between two disks with same capacity, use one with lower number of platters.

http://www.tomshardware.com/reviews/understanding-hard-drive-performance,1557-3.html

High data density is desirable, as it has a positive impact on data transfer performance: the more bits the drive can read concurrently, the faster it is. As a result, a new 3.5" 7,200 RPM hard drive always outperforms an older model. However, access time doesn't benefit from higher storage densities, as the head positioning cannot possibly be accelerated without putting substantial mechanical strain on the components.

If your question were about the physical size of the drives, then yes - a 2.5" 7200 rpm drive is faster than a 3.5" 7200 rpm drive of the same size. The read-write heads do not needs to move as far.

In general I agree everyone else's answers. Given two hard drives with all else being equal the drive with greater data density will outperform the one with lower data density.

I can think of two scenarios where a larger drive capacity is a detriment to performance. In both cases it is not the drive that's the bottleneck but the file system.

• Formatting the drive

This is simply a matter of common sense. Since formating touches every byte on a drive a larger drive capacity will take longer to format. Since this is usually only done during an OS installation its not really a problem. In most cases its unnecessary to perform a full format operation anyway.

• Bumping into the limitations of the file system in-use

The best example of this was the point when drive capacities started to push the limits of the FAT file system. Without getting too technical FAT was designed for disk capacities a fraction of the size of its theoretical limits. FAT16's limit was around 2GB but as partitions approached this limit not only did they waste significant amounts of space but the overall performance of the file system degraded. FAT32 broke the 2GB barrier and performed better than FAT16 but ran into the same problem when drive capacities started approaching its theoretical limit (its around 2TB but this would be laughable to even attempt)

Each file system has different best and worst case running conditions. Modern file systems are designed to at least maintain performance if not improve it as drive capacity grows at the expense under-performing on small drives. A reasonable trade-off considering drive capacities are continuing to grow.

A hdd has a few platters. If both 80g and 500g has the same number of platters. That would mean the OS installed would fall in several platters on the 80G where as 1 or 2 platter on the 500G.

Each platter would have its own read and write. So on the 80G it is serviced by more heads than the 500G. So it is faster.