Problems with Intel 945GM and 1680x1050 resolution

jnerlich · ‎10-17-2007

Hello,

I bought myself a new Samsung SyncMaster 226BW which runs on a 1680x1050 resolution. Unfortunately my laptop with an Intel 945GM graphic controller is not showing me this resolution. I tried powerstrip and followed the instructions in the following threads:

http://softwarecommunity.intel.com/isn/Community/
en-US/forums/thread/30236608.aspx
http://softwarecommunity.intel.com/isn/Community/
en-US/forums/thread/30237794.aspx

All this did not help.

I used the DTD: 7C 2E 90 A0 60 1A 1E 40 30 20 36 00 DA 28 11 00 00 1A.
Regedit shows this value for all DTD_1 and the TotalDTDCount is set to 1.

Do you have any advice what else to do or check to get it working?
Thanks and regards, Jennifer

The results of MonInfo are:

Monitor
Windows description......... Samsung Monitor
Manufacturer description.... SyncMaster
Manufacturer................ Samsung
----------------------------
Plug and Play ID............ SAM027E
Serial number............... HSDP745291
EDID data source............ I2C bus (real-time)
----------------------------
Manufacture date............ 2007, ISO week 29
EDID revision............... 1.3
Display type and signal..... Analog 0.700,0.300 (1.0V p-p)
Sync input support.......... Separate, Composite, Sync on green
Screen size................. 470 x 300 mm (~23")
Power management............ Active off/sleep

Color characteristics
Display gamma............... 2,20
Red chromaticity............ Rx 0,644 - Ry 0,333
Green chromaticity.......... Gx 0,286 - Gy 0,603
Blue chromaticity........... Bx 0,152 - By 0,079
White point (default)....... Wx 0,313 - Wy 0,329

Timing characteristics
VESA GTF support............ Not supported
Horizontal scan range....... 30-81kHz
Vertical scan range......... 56-75Hz
Video bandwidth............. 140MHz
Extension blocks............ n/a
Timing recommendation #1.... 1680x1050 at 60Hz
Modeline................ "1680x1050" 119,000 1680 1728 1760 1840 1050 1053 1059 1080 +hsync -vsync

Standard timings supported
640 x 480 at 60Hz - IBM VGA
640 x 480 at 67Hz - Mac II
640 x 480 at 72Hz - VESA
640 x 480 at 75Hz - VESA
720 x 400 at 70Hz - IBM VGA
800 x 600 at 56Hz - VESA
800 x 600 at 60Hz - VESA
800 x 600 at 72Hz - VESA
800 x 600 at 75Hz - VESA
832 x 624 at 75Hz - Mac II
1024 x 768 at 60Hz - VESA
1024 x 768 at 70Hz - VESA
1024 x 768 at 75Hz - VESA
1152 x 864 at 75Hz - VESA
1152 x 870 at 75Hz - Mac II
1280 x 960 at 60Hz - VESA
1280 x 1024 at 60Hz - VESA
1280 x 1024 at 75Hz - VESA
1680 x 1050 at 60Hz - Samsung
1680 x 1680 at 60Hz - VESA

Raw EDID base
00: 00 FF FF FF FF FF FF 00 4C 2D 7E 02 32 32 45 4D
10: 1D 11 01 03 0E 2F 1E 78 2A D5 1 5 A4 55 49 9A 27
20: 14 50 54 BF EF 80 B3 00 81 80 81 40 71 4F 01 01
30: 01 01 01 01 01 01 7C 2E 90 A0 60 1A 1E 40 30 20
40: 36 00 DA 28 11 00 00 1A 00 00 00 FD 00 38 4B 1E
50: 51 0E 00 0A 20 20 20 20 20 20 00 00 00 FC 00 53
60: 79 6E 63 4D 61 73 74 65 72 0A 20 20 00 00 00 FF
70: 00 48 53 44 50 37 34 35 32 39 31 0A 20 20 00 A9

Display adapter
Adapter description......... Auxiliary port
Adapter device ID........... 0x27A68086
Display settings............ n/a

User/computer information
Registered user name........ SAP
Registered organization..... SAP
Network user name........... D041260
Network computer name....... WDFN00169162A
Windows version ............ Windows XP
Windows build .............. 5.01.2600 Service Pack 2
Installation date .......... n/a

Aaron_B_Intel · ‎10-17-2007

Did you append "37 01" to the end of each DTD_1 value?

7C 2E 90 A0 60 1A 1E 40 30 20 36 00 DA 28 11 00 00 1A 37 01

It's also possible the BIOS is refusing 1680x1050. You can try

7C 2E88 A8 60 1A 1E 40 30 20 36 00 DA 28 11 00 00 1A 37 01

(1672x1050) to get around that.

Are you rebooting after you make the changes to the registry?

Powerstrip's not too useful with Intel graphics unless you're trying to underscan an overscanned monitor. I'd de-install it in case it's playing havoc with your registry.

jnerlich · ‎10-18-2007

Hello Archibael,

thank you very much for your promt reply. I have good news.

I just deinstalled Powerstrip and it is working. I guess as you said it was playing havoc with the registry.

Thank you for your time and help.
Jennifer

7oby · ‎10-18-2007

archibael:

Powerstrip's not too useful with Intel graphics unless you're trying to underscan an overscanned monitor. I'd de-install it in case it's playing havoc with your registry.

I might be wrong, but I understood Ashley Saldanha in such a way, that this psbeta supports intel custom resolutions in a user friendly way:
http://www.entechtaiwan.com/files/psbeta.exe

It's also contained in the most recent stable release 3.75.590:
- Improved Intel GMA custom resolution support

"I only tested this under XP on a i915G and i945G, but you should find the latest build of PowerStrip here supports user-defined, custom resolutions."
http://forums.entechtaiwan.net/viewtopic.php?p=19876#19876

"It is a new capability, added to Build 583 which was posted today."
http://forums.entechtaiwan.net/viewtopic.php?p=19887#19887

This is a direct response to:
"According to Rik's post here (a couple weeks ago), custom settings were not supported on Intel drivers."
http://forums.entechtaiwan.net/viewtopic.php?p=19647#19647

Aaron_B_Intel · ‎10-18-2007

Hey, I'm a fan of Powerstrip, I assure you. Wish we could get full support, but I've never been able to make it work, and evidently Rik has been unsuccessful in getting cooperation from Intel folks on letting him know how to get in and tweak stuff.

It does a great job with helping to figure out the basics of a custom resolution, but actually applying that custom resolution seems to be a bit tweaky. It's why I suggest messing with the registry directly, dangerous as it seems.