The moment I reconnect the internal 'green' drive, things are noticeably slower. As time passes, searches, copies and transfers get ever slower.
The fact that the problem worsens over time strongly implies that this is a software problem.
The SSD is the boot disk. So should the WDC disk be Disk0? Just wondering why Disk Management sees it/puts it first in the order.
That probably has to do with the way the drives are connected internally.
The SATA ports on the motherboard are numbered. Windows probably numbers the drives in order of their SATA port numbers.
And this is what CrystalMark says about the WDC 'green' drive:
Both Windows and CrystalMark seem to think there is nothing wrong with the green drive.
Just to be on the safe side, the WDC internal disk will be disconnected again once this post is sent. I simply don't trust it. Once the new 2TB HDD (ordered from Amazon) arrives, all my porn files from the WDC will be copied across.
If you want to keep using the drive, you can buy an enclosure for it, and turn it into a USB external drive. Then, it will perform like all your other external drives.
Add 2: IDE/AHCI options. System was set to IDE. Changed it to AHCI, but Windows would not start - I just got the black error/options screen. So I changed the setting back to IDE.
I realize that Windows 7 has been out for 3 or 4 years, but it is still very old-fashioned that Windows cannot deal with the AHCI. I had read posts on the internet that this was the case, but I did not believe it until now. On the other hand, the reason you could not install Linux Mint is probably because of the way the IDE interface is implemented by your BIOS. Linux Mint can run on IDE systems, but your drive is NOT an IDE drive, it is SATA. Your BIOS is performing a translation of the SATA interface to IDE so that Windows can understand it. Not only is that extremely old-fashioned (IDE technology was introduced in 1986), but you lose a lot of system performance because of this. SATA was specifically developed as a faster alternative to IDE. Linux Mint should be able to handle an IDE drive, but there is something not quite standard about the way your BIOS is mimicking IDE that is tripping up the Mint installer.
Although Win 7 can run with your green SATA drive configured as an IDE, there is still something about the configuration that Windows is having trouble with. That's what's slowing the system down. Because IDE is such an old technology, it was never designed to handle drives as large as 1 TB (not even close). Although ways of getting around the limits have been developed, I suspect the problem is that your BIOS is trying to interpret a 1 TB SATA drive as an IDE, and the translation is less than perfect.
Owing to a lack of foresight by motherboard manufacturers, the system BIOS was often hobbled by artificial C/H/S [Cylinder, Head, Sector] size limitations due to the manufacturer assuming certain values would never exceed a particular numerical maximum. The first of these BIOS limits occurred when ATA drives reached sizes in excess of 504 megabytes, because some motherboard BIOSes would not allow C/H/S values above 1024 cylinders, 16 heads, and 63 sectors. Multiplied by 512 bytes per sector, this totals 528482304 bytes which, divided by 1048576 bytes per megabyte, equals 504 megabytes.
The second of these BIOS limitations occurred at 1024 cylinders, 256 heads, and 63 sectors, but a bug in MS-DOS and MS-Windows 95 limited the number of heads to 255. This totals to 8422686720 bytes, commonly referred to as the 8.4 gigabyte barrier. This is again a limit imposed by x86 BIOSes, and not a limit imposed by the ATA interface.
It was eventually determined that these size limitations could be overridden with a tiny program loaded at startup from a hard drive's boot sector. Some hard drive manufacturers, such as Western Digital, started including these override utilities with new large hard drives to help overcome these problems. However if the computer was booted in some other manner without loading the special utility, the invalid BIOS settings would be used and the drive could either be inaccessible or appear to the operating system to be damaged.
The take-home point here is that you may have the same problem with the 2 TB drive you have ordered from Amazon, if you install it as an internal drive, configured as IDE. (And you will need to configure it as IDE to work with Win 7).
Now you understand why everyone says Windows is such a crap OS.