There is no "Stereo mix" and "CD player" recording options in the Lenovo ThinkPad R61, T61 (allergedly X61 also, but we haven't confirmed that yet) under Windows XP or Windows Vista.
Those are available in the previous generations of nearly identical machines like T60p
You should contact your Lenovo sales (before you purchase one) and/or support personnel (too late) for the "official" explanation if you feels like it, it is quite funny if you have a sense of humor.
Otherwise, you can see other users' more realistic and down to earth view on various forums
Some claimed it is the difference in hardware.
Is different versions of Analog Device's SoundMAX Integrated Digital HD Audio
HDAUDIO\FUNC_01&VEN_11D4&DEV_1984&SUBSYS_17AA20D7&REV_1004 (T61) vs
[it would be funny if all the new rev. "by design" changes for unspecified reason did is to remove features as some people claimed]
The datasheets from Analog Device seem to say the functionalities are in the hardware.
- Analog mixer supports recording and playback of signals from multiple analog input sources
and/or the change from184.108.40.20626 to 220.127.116.1170 driver the culpit?
It makes you scratch you head why in the new version's
there is a line
HKR,AD1984\\Disable, OutR, 1, 01 ;; Disable Stereo Mix Capture Node
Or there is something funny about Lenovo "new and improved" system board design? Nobody can tell you for sure at this time.
You can also check out users of other manufacturers who pulled the same stunt deal with this situation, some have better luck than others.