Unable to use external display native resolution

Question

Dear all,
Here is the current setup I'm using :
MacbookPro 15", hi res, Mid 2010 with Mac OS 10.6.6, software up-to-date
Apple MiniDisplayPort to VGA Adapter Firmware 1.03
IIYAMA Prolite E2607WSD, a 26" monitor with native resolution of 1920x1200 @ 60Hz
When connecting the MiniDisplayPort to VGA adapter to the VGA cable, the MBP doesn't enable me to set the external native monitor resolution of 1920x1200 with extended desktop. The maximum available resolution the macbookpro is able to diaply is 1920x1080.
What I tried :
-using high performance graphics in the energy saver settings
-using clamshell mode
-using mirroring mode
-reset PRAM
-reset SCM
-delete com.windowserver.plist
-use SwitchResX.app and DisplayConfigX.app to force the native resolution
To make sure that the monitor was correctly behaving, I tried with a PC with WinXP, and I was able to get max resolution of 1920x1200 without an issue. I also tried with a Macbook 2008 with 10.5.6, and with it's own DisplayPort to VGA adapter (the "normal size" one, not the "mini" one I'm using with the MBP), and it worked as well with the native resolution of 1920x1200.
I 'm coming to the conclusion that either the minidisplayport to vga adapter doesn't accept any resolution higher than 1920x1080 or that the one I bought from Apple is not properly working, or that I should use the minidisplay port to DVI adapter (no HDMI here as an input for the monitor)...
I also browsed the forum and found a lot of similar issues, so I guess it's pretty common, but no workaround seems possible.
Does anybody in the community had the same issue and know how to solve it ?
Thanks in advance.
PolCls

Answer 1

Hello BSteely,
I actually tried to get the EDID information and to replicate them as much as possible but everytime I tried a custom resolution, after reboot, SRX will say " the system didn't accept this setup"... and the proper resolution is not available..
See below the data :
DDC block report generated by SwitchResX version 4.2 for display
PLE2607WSD
------------------- RAW DATA ------------------------
0 1 2 3 4 5 6 7 8 9 A B C D E F
0 | 00 FF FF FF FF FF FF 00 26 CD 03 66 21 02 00 00
1 | 0C 14 01 03 68 37 22 78 2A 7B 65 A5 55 48 99 26
2 | 12 50 54 BD EF 80 71 4F 81 80 81 8F 95 00 95 0F
3 | A9 40 B3 00 D1 C0 7D 4B 80 A0 72 B0 2D 40 88 C8
4 | 36 00 26 58 21 00 00 1C 00 00 00 FF 00 31 31 30
5 | 35 36 30 31 32 30 30 35 34 35 00 00 00 FD 00 37
6 | 4C 1D 51 14 00 0A 20 20 20 20 20 20 00 00 00 FC
7 | 00 50 4C 45 32 36 30 37 57 53 44 0A 20 20 00 11
< 00FFFFFF FFFFFF00 26CD0366 21020000 0C140103 68372278 2A7B65A5 55489926 125054BD EF80714F 8180818F 9500950F A940B300 D1C07D4B 80A072B0 2D4088C8 36002658 2100001C 000000FF 00313130 35363031 32303035 34350000 00FD0037 4C1D5114 000A2020 20202020 000000FC 00504C45 32363037 5753440A 20200011 >
{ 0x00, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0x00, 0x26, 0xCD, 0x03, 0x66, 0x21, 0x02, 0x00, 0x00, 0x0C, 0x14, 0x01, 0x03, 0x68, 0x37, 0x22, 0x78, 0x2A, 0x7B, 0x65, 0xA5, 0x55, 0x48, 0x99, 0x26, 0x12, 0x50, 0x54, 0xBD, 0xEF, 0x80, 0x71, 0x4F, 0x81, 0x80, 0x81, 0x8F, 0x95, 0x00, 0x95, 0x0F, 0xA9, 0x40, 0xB3, 0x00, 0xD1, 0xC0, 0x7D, 0x4B, 0x80, 0xA0, 0x72, 0xB0, 0x2D, 0x40, 0x88, 0xC8, 0x36, 0x00, 0x26, 0x58, 0x21, 0x00, 0x00, 0x1C, 0x00, 0x00, 0x00, 0xFF, 0x00, 0x31, 0x31, 0x30, 0x35, 0x36, 0x30, 0x31, 0x32, 0x30, 0x30, 0x35, 0x34, 0x35, 0x00, 0x00, 0x00, 0xFD, 0x00, 0x37, 0x4C, 0x1D, 0x51, 0x14, 0x00, 0x0A, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x00, 0x00, 0x00, 0xFC, 0x00, 0x50, 0x4C, 0x45, 0x32, 0x36, 0x30, 0x37, 0x57, 0x53, 0x44, 0x0A, 0x20, 0x20, 0x00, 0x11, }
Valid EDID block: checksum passed
------------------- MAIN EDID BLOCK -----------------
EDID Version........1.3
Manufacturer........IVM
Product Code........870 (0366) (6603)
Serial Number.......00000221
Manufactured........Week 12 of year 2010
Max H Size..........55 cm
Max V Size..........34 cm
Gamma...............2,20
Display Supported Features:
Power Management: Active off
Display type:
RGB color display
Display is non continuous frequency
Default color space is not sRGB standard
Preferred timing mode includes Native Pixel Format
Input signal & sync:
Analog input with: 0.700V / 0.000V
Composite Sync
Color info:
Red x = 0,646 Green x = 0,283 Blue x = 0,149 White x = 0,313
Red y = 0,335 Green y = 0,601 Blue y = 0,072 White y = 0,329
Established Timings:
720 x 400 @ 70Hz
640 x 480 @ 60Hz
640 x 480 @ 67Hz
640 x 480 @ 72Hz
640 x 480 @ 75Hz
800 x 600 @ 60Hz
800 x 600 @ 72Hz
800 x 600 @ 75Hz
832 x 624 @ 75Hz
1024 x 768 @ 60Hz
1024 x 768 @ 70Hz
1024 x 768 @ 75Hz
1280 x 1024 @ 75Hz
Manufacturer Reserved Timings:
1152 x 870 @ 75Hz
Standard Timing Identification:
#0: 1152 x 864 @ 75Hz (714F)
#1: 1280 x 1024 @ 60Hz (8180)
#2: 1280 x 1024 @ 75Hz (818F)
#3: 1440 x 900 @ 60Hz (9500)
#4: 1440 x 900 @ 75Hz (950F)
#5: 1600 x 1200 @ 60Hz (A940)
#6: 1680 x 1050 @ 60Hz (B300)
#7: 1920 x 1080 @ 60Hz (D1C0)
Monitor Description blocks:
Descriptor #0 - Timing definition:
Mode = 1920 x 1200 @ 59,885Hz
Pixel Clock............. 193,25 MHz Non-Interlaced
Horizontal Vertical
Active.................. 1920 pixels 1200 lines
Front Porch............. 136 pixels 3 lines
Sync Width.............. 200 pixels 6 lines
Back Porch.............. 336 pixels 36 lines
Blanking................ 672 pixels 45 lines
Total................... 2592 pixels 1245 lines
Scan Rate............... 74,556 kHz 59,885 Hz
Image Size.............. 550 mm 344 mm
Border.................. 0 pixels 0 lines
Sync: Digital separate with
* Positive vertical polarity
* Negative horizontal polarity
Descriptor #1 - Serial number:
1105601200545
Descriptor #2 - Monitor limits:
Horizontal frequency range.......29-81 kHz
Vertical frequency range.........55-76 Hz
Maximum bandwidth unspecified
Descriptor #3 - Monitor name:
PLE2607WSD
What do you think are the parameters I should use ?
Thanks in advance;
Paul