True SATA speed?

[mtrox]

I've been Googling around looking for an answer to the question:

What is the real world data transfer speed boost of SATA 1 and/or 2 versus IDE? Most of the discussions I see quickly loose me as they either:

interchange 150 MB/s with 150 Mb/s
dissolve into an argument over theoretical speeds where the drive is connected to some bench test.Here's what I'd like to know:

Is the speed boost significant once it's channeled through the bus of the average business laptop or desktop?
And if the computer is connected to a network that runs through a 10/100 Mb switch, does it really matter in terms of data transfer between nodes?

[Thrax]

Theoretical throughput is 150 MB/s (Megabytes/second). In the real world, they're physically limited by platter densities and rotational velocity. If HDD manufacturers would make a PATA drive to the same specifications as an SATA drive, the speed difference would be within the margin of error; if it wasn't, it could only be chalked up to the fractionally lower bus overhead of SATA.


What about switches?

[mtrox]

That's some of what I read Thrax....that rotational speed is a real limiter. And that if you speed up the RPM's you use more power, create more heat, and shorten the drive's life a bit.

So you're saying there's not a lot of difference. That's my uninformed gut.

What happens with that theoretical 150 MB once it hits the bus and makes its way to the modern 100/1000 Mb NIC card? Once you convert that 1000 Mb to MB.....does it matter at all?