02-21-2009 02:39 AM - edited 02-21-2009 02:58 AM
My T500 has developed a serious problem with the video from the discrete graphics interface being completely corrupted.
I was trying out the dual-monitor capabilities with my L170p monitor. As I used it, I noticed some video corruption, especially on applications dragged between displays. Eventually I decided that it wouldn't really benefit me anyway, and so I reduced the display 2 resolution to the minimum (800 x 600) and disabled the "Extend my Windows desktop onto this monitor" option.
However, the corruption continued and I decided to reboot. Before I could, however, the machine gave a BSOD which was mostly unreadable. Rebooting, the WinXP startup screen was also corrupted; I tried using Fn+F7 to switch to the external display, but it was no better. Trying to log in by fingerprint, the machine BSOD'ed - this text was unreadable, but I did see the word "Parity" in there. From this point, it went from bad to worse. Plugging in the external display and attempting to get to the BIOS with F1 at power-on, I could see there was some text there, but it's mostly unreadable and overlaid with lots of video noise and vertical cyan bars, flashing boxes of all colors, etc.
Somehow, I managed to see enough to get the BIOS to switch to the integrated graphics and was able to boot Windows and install the Intel graphics driver, so the machine is sort of functional again.
However, switching back to "discrete graphics" gives the same problem: no video on the internal LCD, only scrambled video on the external monitor. If I allow Windows to boot with discrete graphics, it BSOD's with a mostly unreadable screen, but it seems to refer to halting Windows to avoid hardware damage and the word "conflict" is in there, too.
Configuration: T500 type 2081-CTO, 4 GB RAM, WinXP SP 3, fully up-to-date with drivers
BIOS Display settings (all other settings are default):
Default Primary Video Device: Internal
Boot Display Device: Thinkpad LCD
Graphics Device: Originally Discrete Graphics, now Integrated Graphics
OS Detection for Switchable Graphics: Disabled
I did wonder if the dual-display configuration somehow mapped the ATI video RAM so that it conflicted with the top of that 4GB of RAM. Removing a 2 GB DIMM didn't help. However, once the machine was successfully rebooted with Windows, the ATI driver wasn't loaded (since the discrete graphics adapter was disabled) and so perhaps whatever was mapped wasn't unmapped? However, I'd expect the graphics memory mapping to be reset on power-up anyway. And since the video is so comprehensively screwed-up on power-up, it's looking more like a permanent hardware failure, in which case the machine will go back under warranty.
Does anyone have any other suggestions on how to proceed?
Solved! Go to Solution.
02-21-2009 04:20 PM
A short piece of additional information: I left the machine overnight with no battery and no charger, to see if anything might reset itself. Switching back to discrete graphics and restarting, this time the internal display came on and the display corruption was initially not so severe - I was able to make out enough of the BIOS configuration text to be able to switch back to integrated graphics without too much trouble, although by the time I got to the graphics options page it was pretty much unreadable. So there was a slight improvement.
02-22-2009 10:06 PM
Thanks, Patrick. That was my conclusion too; after leaving the machine for 30 hours with no battery, I powered it up, switched the BIOS back to discrete graphics and gave it another shot: the result was the same - garbage all over the screen, and this time it didn't even turn on the internal LCD.
So, I've raised a service call, and the machine is going back. However, I'm concerned that there may be a problem with the dual-display operation on this machine, and would caution others against using this feature, especially if they have 4 GB of RAM. If there's the slightest indication of horizontal breakup or corruption of the display, disable the "Extend my Windows desktop onto this monitor" option and pray nothing's fried. Hopefully, either this thread or the information I supply with the machine will make it into Lenovo's internal systems and someone will investigate further.
02-23-2009 08:10 PM
A minor update and kudos for Lenovo/IBM support:
A couple of phone calls to IBM (who service/support Lenovo here) and the machine has been picked up by a courier (within 90 minutes, which is great!). What was particularly good was that the gent from IBM Brisbane asked me at the beginning of our conversation whether I was technical, and when I said "yes", he didn't stuff me around - we got straight to the meat of the problem and had narrowed it down to a hardware problem pretty quickly. I cannot begin to tell you how much that means: in the past, I've had Dell tech support on the phone asking me to reinstall Windows over Linux on a failed hard drive before they would accept that it had failed, and similar nonsense from help desk people who insist on going through a script that doesn't even make sense if the user is completely clueless.
Sounds like this will be a system board replacement, and since it has to be back-ordered (made worse by the CTO nature of the machine) it will be a couple of weeks. Hopefully, I'll be able to check the "Solved" icon then.
03-01-2009 01:22 AM - edited 03-01-2009 01:25 AM
I'm sorry that you had a hardware problem with your T500.
I'm also using T500. My problem is, there is a little appearance corruption when using MSWord 2007 with ATI HD 3650 (upper picture), but it is all right with the intel graphic card(lower picture).
Also, this problem does not exist if I am using the 'extending desktop to two displayers' of the ATI graphics card.
Up to now, it is just the problem of appearance and nothing more.
Any one say something?
03-10-2009 08:37 PM
The machine came back last Friday - the tech had replaced the video chip, and also the keyboard, for some reason. He'd also installed Vista x64; I tried to learn to love it, I really did, but after a few days I decided that the benefits didn't outweigh the compatibility problems I was having with my (admittedly old) version of Lotus Notes. So I've reinstalled XP Pro and everything is now back to normal - although I'm not willing to try the external graphics again on this machine.