Hello @Somnum_Technologies
Are you sure you provide the edid on the 1024x600 screen? I checked the edid information , this screen doesn’t have 1024x600 resolution, please double check.
Established Timings I & II:
IBM : 720x400 70.082 Hz 9:5 31.467 kHz 28.320 MHz
DMT 0x04: 640x480 59.940 Hz 4:3 31.469 kHz 25.175 MHz
DMT 0x06: 640x480 75.000 Hz 4:3 37.500 kHz 31.500 MHz
DMT 0x09: 800x600 60.317 Hz 4:3 37.879 kHz 40.000 MHz
DMT 0x0b: 800x600 75.000 Hz 4:3 46.875 kHz 49.500 MHz
DMT 0x10: 1024x768 60.004 Hz 4:3 48.363 kHz 65.000 MHz
DMT 0x12: 1024x768 75.029 Hz 4:3 60.023 kHz 78.750 MHz
DMT 0x24: 1280x1024 75.025 Hz 5:4 79.976 kHz 135.000 MHz
Standard Timings:
DMT 0x15: 1152x864 75.000 Hz 4:3 67.500 kHz 108.000 MHz
DMT 0x23: 1280x1024 60.020 Hz 5:4 63.981 kHz 108.000 MHz
DMT 0x2f: 1440x900 59.887 Hz 16:10 55.935 kHz 106.500 MHz
DMT 0x3a: 1680x1050 59.954 Hz 16:10 65.290 kHz 146.250 MHz
DMT 0x53: 1600x900 60.000 Hz 16:9 60.000 kHz 108.000 MHz (RB)
DMT 0x1c: 1280x800 59.810 Hz 16:10 49.702 kHz 83.500 MHz
DMT 0x55: 1280x720 60.000 Hz 16:9 45.000 kHz 74.250 MHz
DMT 0x2a: 1400x1050 59.978 Hz 4:3 65.317 kHz 121.750 MHz
Detailed Timing Descriptors:
DTD 2: 1920x1080 60.000 Hz 16:9 67.500 kHz 148.500 MHz (698 mm x 392 mm)
Hfront 88 Hsync 44 Hback 148 Hpol P
Vfront 4 Vsync 5 Vback 36 Vpol P
DTD 3: 1920x1080 74.973 Hz 16:9 83.894 kHz 174.500 MHz (698 mm x 392 mm)
Hfront 48 Hsync 32 Hback 80 Hpol P
Vfront 3 Vsync 5 Vback 31 Vpol P
DTD 4: 1280x720 60.000 Hz 16:9 45.000 kHz 74.250 MHz (698 mm x 392 mm)
Hfront 110 Hsync 40 Hback 220 Hpol P
Vfront 5 Vsync 5 Vback 20 Vpol P
DTD 5: 720x480 59.940 Hz 3:2 31.469 kHz 27.000 MHz (698 mm x 392 mm)
Hfront 16 Hsync 62 Hback 60 Hpol N
Vfront 9 Vsync 6 Vback 30 Vpol N
It is the Raspberry Pi HDMI screen with relolution 1024x600.