60Hz SXGA+ success on X61

[Bibin]

My main gripe with the X61, SXGA+ or even XGA, is that it is stuck at 50Hz. Sometimes the OS will tell you it is at 60Hz, but the dropped frames and slower vblank-synchronized content makes it clear that it is not the case.

I have the middleton SXGA+ BIOS installed, which respects the EDID information from the panel. I have an HV121P01 panel, and even in the datasheet the EDID information clearly shows the detailed timing specifications for a 50Hz refresh. A few "standard timing" options are selected, like the industry standard 640x480 and 1024x768 resolutions, but all of them seem to respect the panel timings in the first detailed block. Since the LCD itself has no scaler I suspect the graphics hardware uses the detailed block to determine what the LCD can do, and will do scaling to that specification on its own.

All I really had to do in the end was take the pixel clock, multiply it by 6/5, put it back, and fix the checksum. The next step is to flash it to the EEPROM in the display.

Many celebrate Powerstrip as a paid utility to do that. The registered version could read the EDID, but claimed it could not find a valid device to write to. An open source utility called edid-rw could also read it, but writes failed silently. When I read back the EDID, it still had the original data after re-writing.

I determined that the EDID chip's WP pin (write protect, active high) needed to be grounded. I lifted pin 7 off the board and put a jumper to ground. After that, Powerstrip still failed to see it, but the linux edid-rw utility worked perfectly.

After flashing the EDID, I rebooted, and I had 60Hz! No fancy config, nothing crazy. It just works like any other laptop that supports the industry standard refresh of 60Hz

So, I'm glad this glaring irritating issue is now fixed. If you want the modified EDID, it is here:

http://mikejmoffitt.com/edid-sxga60.bin

I am sure someone will ask, so I'll address this now: "LCDs don't flicker, so why do you care about the refresh rate?"
The reason is that I develop some games and some audiovisual applications that may synchronize to the refresh of the display, as they are intended for use on an NTSC-timing-derived monitor, which invariably refreshes around 60Hz. At 50Hz, the content must either be slowed down, or frameskipping must occur. The former is slow, and the latter is unpleasant, with jerkiness and possibly tearing occuring.

[RealBlackStuff]

What if you would take that machine to a country with 50Hz, such as the whole of Europe?

[Bibin]

What if you would take that machine to a country with 50Hz, such as the whole of Europe?

If you mean the X61 laptop, then nothing, the computer does not care about the refresh rate of displays not attached to it, and the frequency of the AC mains has nothing to do with it at all... as for development of things expecting NTSC timings, they'll run at 5/6 their intended speeds. I do not care for PAL regions so having my computer run at a refresh rate that matches most displays elsewhere in the world makes sense to me.

[pkiff]

Congrats on figuring out this wonky refresh rate issue for the SXGA+ screens in the X61's. And thanks for sharing the details on your fix.

[mdancer]

Just a frendly comment that increasing of the refresh rate could possibly lead to the decrease in panel life. Atleast my QXGA from t60 started to die after a few years at 60Hz.

[MrMaguire]

Cool mod! When I had my X61s I wondered what the deal was with the screen being 50Hz.

[Bibin]

Just a frendly comment that increasing of the refresh rate could possibly lead to the decrease in panel life. Atleast my QXGA from t60 started to die after a few years at 60Hz.

For an odd panel like the QXGA ones, I'd bet they designed it around the relatively low refresh for a reason on there. For the various Boe-Hydis panels, I'm almost positive the X61t ignores the EDID and runs at 60Hz anyway, so I'm not so worried. We'll see how it turns out over time.

Regardless, if this mod is done to the XGA ones with EDID (and the Middleton BIOS installed to let it actually USE the EDID) then we can expect it to be fine, since those panels in other laptops (and the X61t) run at 60Hz.

[xiphmont]

So, I'm glad this glaring irritating issue is now fixed. If you want the modified EDID, it is here:

http://mikejmoffitt.com/edid-sxga60.bin

Ooooh and well done.

[RMSMajestic]

Congratulations!!!!
Have you tried to reinstall the Operating system or use the screen on another X61t? Cos I once somehow had 60Hz but then after reinstallation, it's gone

[Bibin]

Congratulations!!!!
Have you tried to reinstall the Operating system or use the screen on another X61t? Cos I once somehow had 60Hz but then after reinstallation, it's gone

Nope, the Windows and Linux installs I had both were completely okay with it. I did pop a drive from another computer in there, and it saw 60 Hz just fine. What I did didn't touch the OS at all, so that should not be related.

I haven't tried an X61t (don't have one) but I imagine the process would be exactly the same.

I have had Windows report 60Hz before, but it was lying, which is evident when you run a test or run any 60Hz content. That is likely what happened to you before.

[raket]

Any possibilities to get to work on X60 as well?

Best Regards

[Bibin]

Yes, I think this should work just the same on the X60. The only restriction is that you must get the X60 to respect EDID data. With the stock bios, I believe the X61 use a generic 1024x768 EDID stored in the Video BIOS, and the middleton SXGA+ bios is really more of a "middleton display EDID BIOS". If the X60 is like that, you will have to do that BIOS update as well.

So, there are really two components:
-Get your ThinkPad to respect the display's EDID
-Write the modified EDID to your display using edid-rw or any other I2C writing tool. (I have NOT gotten PowerStrip registered to work so I won't tell you to do it)

[Qing Dao]

Wow, this is awesome! Thank you so much, now I want to upgrade my X61!

[Bibin]

Wow, this is awesome! Thank you so much, now I want to upgrade my X61!

Glad you are enjoying it. I am thinking of putting together a bootable Live CD that has everything you need, ready to go. If I get a dump of the XGA EDID, I can make a 60Hz modification for that as well - the only needed change is really taking the existing pixel clock for 50Hz, and multiplying it by 1.2, and putting it back.