I'm happy to say I'm posting this from my gaming laptop that has given me so much frustration for over a year and I just needed a place to vent about my trials and tribulations, and the heck of a learning process of someone that doesn't really know a ton about computer programing and hardware. I bought this laptop.... well, desktop replacement is more accurate as a 12 lb heat machine isn't exactly something you want sitting on your lap. When I bought it, it was top of the line, custom built from a company called Pro-Star. Think Alienware power, for a better price. Actually, even Alienware couldn't match the power of this rig at the time. Put on a pot of coffee, this is gonna be a long one and involves throwing the graphics card in the oven at 385 F for 9 minutes....
Long while back, my backlight would occationally flicker for a split second. The problem got progressively worse and I was thinking it's a hardware problem. The image was always ok, and the VGA output to another monitor was fine, only the light in my lid was out. I did some minor diagnosing and after talking to several people, we figured it was the backlight's power inverter going bad. Took some digging, but I eventually found one to replace it, but that didn't work. I then took it to a shop that ran a battery of tests on it and they too thought it was the original inverter and tried my new (to me, bought used from some place in Asia so quality could have been sketchy). They put in the new one and it seemed to work and they even left it on over night and kept on working. After a few more tests and a couple hundred $$$ later, I had it back. It worked a grand total of about 3 hours before it died again on me.
I couldn't get it to come on completely, but it very rarely would, so I know the light itself wasn't the culprit and was wondering more about the inverter. One thing my mate did notice (and surprised I didn't) was that there was a time I was running it at a con, doing one of my light shows with the VGA out to a projector with 3D animations running and the backlight kicked on. The program didn't need much manual input, so I had planned to just use a flashlight if I needed to do something. Then when I got a new program for that stuff that I was testing at home on my tv, the light came on again after using it for about 30 min. In both cases, it stayed on. Putting two and two together, she was thinking that had something to do with it. About that time is when I saw Mylo's thread on here about a similar problem. In his case, it was a driver issue, so I started looking down that path. This problem had actually been showing signs of both driver and mechanical failure, so didn't know which way to go.
Back to Google I went, tracking down various issues around drivers and specifically the ACPI programing that controls what the lid switch does (I.e. if it just kills the light, puts the laptop to sleep/hibernate, etc). I tried some of the tricks they mention and thought I was on the right track at one point. I uninstalled the "ACPI LID" in the device manager, letting the computer reboot, reinstall it, then reboot again. After it rebooted the second time, the light came on within a few minutes but then went back out. I was thinking maybe it was the switch itself that was faulty. Mind you, this one doesn't have an exposed button I could toggle to see if it was sticky. I was at a loss for a while because I couldn't find it, and even the shop couldn't find it. Granted, it's not every day that you see a system like mine and it always turns heads just from its sheer size even though it has a basic finish to it. So I didn't fault the shop for that.
While I was digging through the web on the software issues, I came across a file with the service manual for my system and printed it out. Tired of looking at the software stuff for a while with no luck, I went back to the mechanical route and went over the parts lists, assembly diagrams, and PCB schematics. This is where I'm so glad I had taken drafting and design for college. One of my classes was on printed circuit boards, both how to read a basic schematic and then how to fit the parts on the PCB itself. While I hated that class with a passion, I never would have been able to make heads or tails of that manual otherwise. It took a while for me to figure out were the switch was and I never did find any sort of switch at first. Then, one day while I was on Second Life to pay my land rent, the light popped on for me. I had heard that my system may have a magnetic switch, so I started running a magnet around the lid and base, eventually making the light flicker. After centering in on where it is, I come to find out the magnetic "switch" is an ant sized microchip that isn't directly labeled as such. I figured it out with the help of the schematics too, but that seemed to be working pretty much fine. So from there, I started tracing all the circuits back from it and following pretty much anything having anything to do with the backlight to look for loose connections and such. Keep in mind, you can't just pull the top panel off to access the motherboard. You have to pull screws off the bottom, the LCD screen, the keyboard, and another little pannel under that just to find some hidden screws, as well as remove the HDD because one is buried under it as well and then pull it apart like a 3D puzzle. Only in this case all the pieces seem like they have to fit together at the same time and not piece by piece.
Didn't find anything this time either, so put it all back together and put it away for a while again. Time comes around to pay SL rent again, so I hop on with my trusty little flashlight so I can see what I'm doing and the light kicks on again. This time I go back to look at some more info on ACPI to see if I can find a way to lock the light into the ON position regardless of what the lid position is doing. Then the light kicked off again. So I go back to SL to finish up there so I can call it a night. Light comes on. I scratch my head, and go back to the ACPI research. Light goes off. At this point, I now realize SL has something to do with it too. I know I'm getting somewhere now at least. In either case, I wrap up and pack it away again.
I have also been conversing with a couple other computer savvy people I know and I mention to one of them about the fact SL causing the light to stay on. He also remembers me telling him about it coming on sometimes when running dual displays, and suggests it may be a bad solder joint. His theory was that when I'm running dual displays or gaming, the graphics card is heating up, expanding the parts enough to make the connection again, letting the light kick on. He had a similar issue with one of his laptops and told me about how he baked the card to get it working again. It actually did make some sense, so next chance I had, I fired it up and put on SL. Sure enough, within about 30 seconds, the light popped on. I opened up a monitoring program as I tested this, and pretty much any time I got the GPU above 160 F, the light would kick on shortly after. Reducing the load by minimizing the game would let the temps drop and then the light would go back off. I double checked the schematics, and sure enough, there is one pin on the VGA card slot labeled something to the effect of enable backlight.
I also read up on the idea of baking the graphics card. For those that don't know (assuming you're still reading by this point.
), it's a DIY way of reflowing the cold solder connection on a PCB. Basically, it's not uncommon for the connections between the chips and the boards to have micro-cracks in the solder from the factory. As it ages, they get worse and open up, causing a failure. By putting it in your oven and baking it (make sure it's RoHS compliant lead free or you risk toxic fumes and/or contaminating your oven), you soften the solder and allows it to essentially melt the crack together. There's more to it than that, so make sure you research just how to do it if you have a problem that you think this may help fix. It's not meant to be the first, but rather the last ditch effort before considering a PCB to be completely gone and results may not be permanent.
Before I did this, I was thinking about trying to replace it with a card one generation newer I had on hand already just to test the idea of it being the graphics card itself. That one was from a computer that we thought was also dead, but now lives on its own, so I just did some inspecting on mine. In the process, I also had to pull one of my memory chips to verify what version my MOBO was (this becomes important later on) if I tried to swap cards. When I put it all back together, I tried to boot the system again just to see if maybe the loose connection was with the card or something itself. It didn't even freaking POST. Crap. I figure maybe I jarred something loose on the graphics card, so I pulled it out and decided to try and bake it. After doing so, the system still wouldn't even POST. I put it away for a few days to let my frustration die down some until tonight. I was wondering if maybe the memory chip had something to do with it, so I pulled it out and powered up the system with just the one other chip left in. It started to boot right up, and the light was on to boot. To see if it was just a bad seat from the first time I pulled it or if the chip itself went bad, I put it back in and booted up again just fine.
So now it seems like my system is back to full operation and now I can really get back in to my gaming. I'm curious as to what might have happened with that memory chip that caused it not to POST, considering it's not like there's really any play in it once it's latched in place. Other than that, the biggest thing I've learned from this whole ordeal is I no longer question why computer techs charge so much. This stuff is complicated!
In closing, I'd just like to say... I'm sure Hoagiebot would be proud of this post.