1 x Promise Ultra 100 IDE Controller card
1 x spare 30GB IBM drive that has worked perfectly for 5 years
1 x rounded cable (new, but I think it's reliable)
Add them all together, format the disk, copy 23GB of content onto it, run chkdsk.
I decided to start a check as I began copying the content. I got:
I:\>chkdsk I:
The type of the file system is NTFS.
Volume label is TEST.
WARNING! F parameter not specified.
Running CHKDSK in read-only mode.
CHKDSK is verifying files (stage 1 of 3)...
File verification completed.
CHKDSK is verifying indexes (stage 2 of 3)...
Index verification completed.
CHKDSK is verifying security descriptors (stage 3 of 3)...
Security descriptor verification completed.
30017420 KB total disk space.
484032 KB in 6 files.
16 KB in 13 indexes.
0 KB in bad sectors.
66920 KB in use by the system.
65536 KB occupied by the log file.
29466452 KB available on disk.
4096 bytes in each allocation unit.
7504355 total allocation units on disk.
7366613 allocation units available on disk.
I ran it again after a while, the disk was about half full, and got:
I:\>chkdsk I:
The type of the file system is NTFS.
Volume label is TEST.
WARNING! F parameter not specified.
Running CHKDSK in read-only mode.
CHKDSK is verifying files (stage 1 of 3)...
File verification completed.
CHKDSK is verifying indexes (stage 2 of 3)...
Index verification completed.
CHKDSK is verifying security descriptors (stage 3 of 3)...
Security descriptor verification completed.
CHKDSK discovered free space marked as allocated in the
master file table (MFT) bitmap.
CHKDSK discovered free space marked as allocated in the volume bitmap.
Windows found problems with the file system.
Run CHKDSK with the /F (fix) option to correct these.
30017420 KB total disk space.
16444224 KB in 113 files.
68 KB in 17 indexes.
0 KB in bad sectors.
67032 KB in use by the system.
65536 KB occupied by the log file.
13506096 KB available on disk.
4096 bytes in each allocation unit.
7504355 total allocation units on disk.
3376524 allocation units available on disk.
And now that all the content is across, I get the same message (actually, now it's gone again - how odd). I'm fairly certain the controller card must be playing up, some kind of intermittent fault, and I'm very confident that the 4 disks that used to be plugged into it are perfectly okay - the random errors are now gone, and I can read the content back perfectly in another system. There's still a small chance it's the new cables (although I had been able to copy the content onto all 4 disks without any trouble for the last few months, so I think it's just trouble reading data via the controller), but I'll order a new card and see if I still have trouble. At worst, I'll have wasted £18 on a card, which I could always use in another system. I might even try out a spare IDE cable in the morning, just to rule it out for certain.