PC: Harddisk question

[Blomberg]

Two HHD's:

One Western Digital 80gb w. 8mb cache, 7200 rpm, ATA100

One Samsung 20gb w. ?mb cache, 5400 rpm, ATA100

The 80 gig WD currently resides in my PC (the 20 gig used to - quite a speed difference there)


Here's the question:

If I add the second one (the 20 gig) to the same IDE channel (as slave) as the (fast) WD, will it slow down the WD?

I've heard that if you have two devices on the same channel, they will run at the speed of the slowest, but does that apply in this case or is that only if one is eg. ATA66 and the other is ATA100?

[whabang]

They will both run at their maximum speeds.
It is not possible to mix ATA 66 and 33 ( or 100 or 133 or whatever... :-D ), but two drives with ATA 100 will both work with optimal speed.
This is why a standard CD-ROM has ATA 100 support, if it didn't, it would slow down the system.

[Blomberg]

They will both run at their maximum speeds.

Yes, that's what I thought too.

It is not possible to mix ATA 66 and 33

No, but if you hook up an ATA33 drive and an ATA66 drive to the same channel, the ATA66 one will drop down to ATA33 (if it supports it), at least that's what I've been told.  :-|

[whabang]

No, but if you hook up an ATA33 drive and an ATA66 drive to the same channel, the ATA66 one will drop down to ATA33 (if it supports it), at least that's what I've been told. :-|

Yep, that's what I meant... ;-)

[Blomberg]

Ok, so ATAwhatever is the only thing one should be wary of when mixing and matching HDD's then?
Cache sizes and physical speed don't mean anything at all?

[whabang]

Exactly.
PIO mode can also be used in the same way, but it takes much more CPU power...

[Blomberg]

Thanks.

Well, I guess I can't put off opening the beast any longer  :-(

/me dreads the amount of dust and cobwebs in there  :-o

[blobrana]

Don`t forget about DMA...

http://mysite.freeserve.com/blobrana/cucd/dma.htm
 :-D