If you're running Win2k/XP, I can give you a real easy solution. You'll have to uninstall your current video drivers and reinstall them to enable the custom res' though. What you have to do is edit the Nv4_disp.inf file in the drivers folder. Find the section for your video card (the Geforce3 is the nv20) and add the desired resolutions. Here's a sample from my Nv4_disp.inf (this is the 32bit section):
HKR,, NV20_Modes, %REG_SZ_APPEND%, "32 640 480 60 70 72 75 85 100 120 0"
HKR,, NV20_Modes, %REG_SZ_APPEND%, "32 856 840 60 70 72 75 85 100 120 0"
HKR,, NV20_Modes, %REG_SZ_APPEND%, "32 960 720 60 70 72 75 85 100 120 0"
HKR,, NV20_Modes, %REG_SZ_APPEND%, "32 720 480 60 70 72 75 85 100 120 0"
HKR,, NV20_Modes, %REG_SZ_APPEND%, "32 768 576 60 70 72 75 85 100 120 0"
HKR,, NV20_Modes, %REG_SZ_APPEND%, "32 304 224 60 70 72 75 85 100 120 0"
HKR,, NV20_Modes, %REG_SZ_APPEND%, "32 608 448 60 70 72 75 85 100 120 0"
HKR,, NV20_Modes, %REG_SZ_APPEND%, "32 384 224 60 70 72 75 85 100 120 0"
HKR,, NV20_Modes, %REG_SZ_APPEND%, "32 768 448 60 70 72 75 85 100 120 0"
HKR,, NV20_Modes, %REG_SZ_APPEND%, "32 400 256 60 70 72 75 85 100 120 0"
HKR,, NV20_Modes, %REG_SZ_APPEND%, "32 395 253 60 70 72 75 85 100 120 0"
HKR,, NV20_Modes, %REG_SZ_APPEND%, "32 395 254 60 70 72 75 85 100 120 0"
HKR,, NV20_Modes, %REG_SZ_APPEND%, "32 304 224 60 70 72 75 85 100 120 0"
HKR,, NV20_Modes, %REG_SZ_APPEND%, "32 288 224 60 70 72 75 85 100 120 0"
HKR,, NV20_Modes, %REG_SZ_APPEND%, "32 256 224 60 70 72 75 85 100 120 0"
HKR,, NV20_Modes, %REG_SZ_APPEND%, "32 320 224 60 70 72 75 85 100 120 0"
HKR,, NV20_Modes, %REG_SZ_APPEND%, "32 240 224 60 70 72 75 85 100 120 0"
HKR,, NV20_Modes, %REG_SZ_APPEND%, "32 320 200 60 70 72 75 85 100 120 0"
HKR,, NV20_Modes, %REG_SZ_APPEND%, "32 320 240 60 70 72 75 85 100 120 0"
HKR,, NV20_Modes, %REG_SZ_APPEND%, "32 400 300 60 70 72 75 85 100 120 0"
HKR,, NV20_Modes, %REG_SZ_APPEND%, "32 480 360 60 70 72 75 85 100 120 0"
HKR,, NV20_Modes, %REG_SZ_APPEND%, "32 512 384 60 70 72 75 85 100 120 0"
HKR,, NV20_Modes, %REG_SZ_APPEND%, "32 640 400 60 70 72 75 85 100 120 0"
HKR,, NV20_Modes, %REG_SZ_APPEND%, "32 800 600 60 70 72 75 85 100 120 0"
HKR,, NV20_Modes, %REG_SZ_APPEND%, "32 1024 768 60 70 72 75 85 100 120 0"
HKR,, NV20_Modes, %REG_SZ_APPEND%, "32 1152 864 60 70 72 75 85 100 120 0"
HKR,, NV20_Modes, %REG_SZ_APPEND%, "32 1280 768 60 70 72 75 85 100 120 0"
HKR,, NV20_Modes, %REG_SZ_APPEND%, "32 1280 960 60 70 72 75 85 100 120 0"
HKR,, NV20_Modes, %REG_SZ_APPEND%, "32 1280 1024 60 70 72 75 85 100 120 0"
HKR,, NV20_Modes, %REG_SZ_APPEND%, "32 1600 900 60 70 72 75 85 0"
HKR,, NV20_Modes, %REG_SZ_APPEND%, "32 1600 1024 60 70 72 75 85 0"
HKR,, NV20_Modes, %REG_SZ_APPEND%, "32 1600 1200 60 70 72 75 85 0"
HKR,, NV20_Modes, %REG_SZ_APPEND%, "32 1920 1080 60 70 72 75 85 0"
HKR,, NV20_Modes, %REG_SZ_APPEND%, "32 1920 1200 60 70 72 75 85 0"
HKR,, NV20_Modes, %REG_SZ_APPEND%, "32 1920 1440 60 70 72 75 85 0"
HKR,, NV20_Modes, %REG_SZ_APPEND%, "32 2048 1536 60 70 72 75 85 0"
I added all the extra resolutions so I could run my old arcade games in MAME fullscreen without bilinear filtering.
For adding resolutions Windows 98/ME, have a look
HERE.
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Sir, are you classified as human?
Negative, I am a meat popsicle.