Multi-CPU - can't switch off?

[midflight]

Hi,

A query about batch-encoding:

When using the multi-encoder (say to convert from WAV to FLAC & MP3 at the same time) I get the option to select "Multi-CPU" on or off.

But when using a single-encoder (eg converting from FLAC to MP3) I don't get the option, and it defaults to trying to encode using Multi-CPU... even though I only have one CPU!?

Is this normal?

[LtData]

What CPU do you have? Do you have two CPU graphs in Task Manager?

[midflight]

Sorry, you might be right.

I have a Dell Dimension 5150, which is not dual-core. I assumed this meant it does not have 2 x CPUs, but in Task Manager I do indeed have 2 x CPU graphs...

[LtData]

You probably have a Hyperthreaded Pentium-4, which is one CPU and one virtual CPU.

[midflight]

OK, thanks. Interesting - a virtual CPU. How is that done? Using RAM?

Anyway, in that case, is it best to have the multi-cpu option switched on or off?
Or won't I notice much difference?
(I can't test it, as it won't let me switch it off)

[LtData]

See here for how Hyperthreading works: http://en.wikipedia.org/wiki/Hyperthreading
As for speed, you would probably be better off with Multi-CPU on than off, but you could test this yourself to find out for sure if you use the Multi-Encoder codec, which lets you turn the multi-CPU on or off.

[Spoon]

Just intel marketing...