DMESG Message re: 'Cable Bits'

Toods · 04-15-2006, 04:32 AM

I have two PCs with Slackware installed. At boot, each gives a message about 'cable bits' that I do not understand.

Here is the relevent part from DMESG output:

Code:

NFORCE2: IDE controller at PCI slot 0000:00:09.0
NFORCE2: chipset revision 162
NFORCE2: not 100% native mode: will probe irqs later
NFORCE2: BIOS didn't set cable bits correctly. Enabling workaround.
NFORCE2: BIOS didn't set cable bits correctly. Enabling workaround.
NFORCE2: 0000:00:09.0 (rev a2) UDMA133 controller
    ide0: BM-DMA at 0xf000-0xf007, BIOS settings: hda:DMA, hdb:DMA
    ide1: BM-DMA at 0xf008-0xf00f, BIOS settings: hdc:DMA, hdd:DMA

I do not experience any obvious problems with operation of the PC's but I would be pleased if someopne could explain to me the meaning of this message and also tell me if there is any way that I can overcome it.

Thank you.

mdarby · 04-15-2006, 08:07 AM

Are you using 80 or 40 pin IDE cables?

Toods · 04-15-2006, 08:33 AM

Quote:

Originally Posted by mdarby

Are you using 80 or 40 pin IDE cables?

Thank you for replying.

I'm using the Akasa 'Rounded Ultra ATA133/100/66 IDE Cables'.

I guess that these would be 80 pin.

Is this probably the cause of the messages?.

mdarby · 04-15-2006, 10:59 AM

I would assume, but I'm not sure. If this is the case, you can safely ignore the messages.

ledow · 04-16-2006, 08:06 AM

As a general rule, if Linux tells you "enabling workaround", there's no need to worry. It usually means that the BIOS is out-of-date or slightly faulty but that Linux KNOWS that and has taken account of it to make sure it's not a problem.

Probably updating your motherboard BIOS would get rid of this messages, possibly not though. Either way doesn't matter - Linux detected the problem, fixed it and merely told you as a courtesy.

Other "workaround" messages in the kernel are usually the same - things like CPU bugs (the infamous Penntium FDIV bugs etc.), receiver locks within older EtherExpress Pro 100 network cards.

I'd say there's a possibility that updating the BIOS or the Linux kernel or using 80-pin IDE cables throughout would fix these messages if they annoy you but that they are in fact completely harmless.

Toods · 04-16-2006, 11:12 AM

Quote:

Originally Posted by ledow

I'd say there's a possibility that updating the BIOS or the Linux kernel or using 80-pin IDE cables throughout would fix these messages if they annoy you but that they are in fact completely harmless.

Thanks for your reply.

As I said earlier, I am not experiencing any problems, so no need for any action as long as nothing is seriously wrong.

One of my PCs exhibiting the phenomenon is an Abit NF7 which already has one of the latest BIOSs (modded). the second is an Abit AN7 which also has one of the last BIOSs released.

Both are running the Linux 2.6.16 kernel which is quite new.

It is the IDE cables that I still wonder about. They are all the 'rounded' ones that are commercially available. I wonder if these are not particularly good in terms of screening or capacitance.

What do you mean by 80-pin cables?. All my rounded cables will be 80-core, but I assume that the connectors can only be 40-pin.