As advised in several threads on this topic, until recently I used driver pack 126.96.36.19906 for the ATI 7500 graphics on my T42 running W7, although the lack of an exact driver match among those offered made me choose "RADEON 7500 Family (Microsoft Corporation - XDDM)" one back then. I've had no BSODs or any other major issues ever since, although the screen won't turn off upon inactivity timeout for some reason (to be exact it'd start turning off and at the very next moment would return back to normal) - not sure if it's caused by the wrong driver (desktop 7500 version I suppose?) or something else.
After recent W7 reinstall I decided to try "ATI Mobility Radeon 9000 (Microsoft Corporation - XDDM)" for a change, which IIRC is another well tested safe choice. So far so good (the screen turn off issue went away) although one thing was hurting my perfectionist's eye: adapter name mismatch in Device Manager > Display Adapters view; besides that, some (not all) system info applications display 9000 as my graphics adapter, apparently just following "wrong" name w/o checking the actual HW.
So I've cloned the 9000's entry in atiixpag.inf:"ATI MOBILITY RADEON 9000 (Microsoft Corporation - XDDM)" = ati2mtag_M9, PCI\VEN_1002&DEV_4C66&SUBSYS_011D1028
and changed the name and HW IDs in it to my 7500's ones while keeping it pointed at the same driver ati2mtag_M9:"ATI MOBILITY RADEON 7500 (Microsoft Corporation - XDDM)" = ati2mtag_M9, PCI\VEN_1002&DEV_4C57&SUBSYS_05301014
Now during manual driver installation/update W7 finds the "right" driver straight away and displays it as a compatible one:https://s23.postimg.org/d2c1ox0d7/AMD_ATI_6_14_10_6606_With_Mobility7500_Added.png
Still no issues so far, which is not surprising as it's the very same driver as for 9000.
Feel free to comment, e.g. if there are any risks in doing it this way or if something else is also worth amending besides the name and HW IDs, etc.
Thanks in advance!