On Thursday 10 March 2005 12:43, Christophe Branchereau wrote: > ide: Assuming 33MHz system bus speed for PIO modes; override with idebus=xx > > A quick look on google told me that the system bus speed of this model is > 66MHz, as http://www.apple-history.com specifies. > > Isn't it degrading disk performances a lot? > As the dma mode that was set to 16 Bits by default, for example.
Hmm.. interesting. I've noticed that message on my x86 machine, but I never spotted it on my iBook. Turns out I have it too. I would have expected the powermac controller to recognise the ppc laptop models (at least) and to know what they can handle. Guess not :) Here's what the kernel driver says on it (leaving out the x86-specific stuff): "idebus=xx" : inform IDE driver of VESA/PCI bus speed in MHz, where "xx" is between 20 and 66 inclusive, used when tuning chipset PIO modes. If in doubt, use idebus=33 for PCI. Bigger values are safer than smaller ones. Problem is, it says nothing about what actually happens with different values :( Worth noting here that you should probably be aiming for DMA rather than PIO, if your iBook can do DMA IDE transfers. -- Lee. -- To UNSUBSCRIBE, email to [EMAIL PROTECTED] with a subject of "unsubscribe". Trouble? Contact [EMAIL PROTECTED]
