Cannot add Custom Resolutions to HD4670 Mobility

[p377y7h33f]

have been trying for days...

this is an old MXM-III laptop - Alienware m5750, 17" WUXGA on 945 Mobile chipset, Windows 7 x64. the HD4670 came from another laptop, but works fine with absolutely no issues.

first, i tried CRU, then CRU with Pixel-Patcher, then ATI Tray tools, then Afterburner, then RadeonPro, then refresh force. absolutely no effect! i tried with Catalyst 13.9 that was installed through device manager with no extras. i tried with the latest CCC and Catalyst 13.9 installed through Install Manager. no luck!

monitor refresh rate never changes! list of valid modes for HD4670 never changes! in Windows in the Monitor Properties tab the "Hide modes that monitor can't display" checkbox is greyed out. in CCC only the resolutions that are in HD4670's "valid modes" list are available. i haven't even been able to add 1440x900@60Hz. nothing!

tried everything. what's locking me out???

EDIT: finally found a way to add resolutions by editing the registry. still can't get any with higher refresh rates. even if it's 61Hz - it just won't show up in CCC. should i try actually editing the EDID?

[ToastyX]

I really don't know. AMD's driver should support EDID overrides with the HD 4670, and that laptop doesn't have switchable graphics, so there must be some other limitation that I don't know about.