Originally posted by: Slickone
What happens if problems do occur w/ rounded cables, just slower xfers because of having to re-read or write bad data, or permanent data corruption?
In the case of WinXP if the OS detects bad data integrity (CRC check, I assume) it bumps the transfer speed down a notch, i.e. DMA5 to DMA4. And it drops it again if it detects more errors. In essence it slows down the transfer rate to protect the data.
I first noticed it because things seemed a little slow so I checked my DMA settings and they were at "PIO" on the Primary channel:Q. I looked in Event Viewer and found a series of error messages that talked about something being wrong with IDE device (0) or something (I don't remember the exact message, it was a year ago). I did some MSKB research and some trouble shooting and decided to replace my rounded IDE cable on that channel with a flat ribbon cable. I got no more errors

. I put the rounded cable back in and started to get Event Viewer errors again

. RMA'd the cable (it was a Coolermaster silver braided 18" two device cable) and tried the new one. Got errors with it too. Put back the flat IDE cable and have been running fine with zero IDE Device errors ever since.