Another Dell XPS M1730 with failed GPU, but this one is different.
Got this beast to look at from a friend of mine. As opposed to the one he gave me last year (the one that turned out to have a bad GPU connector out of all things), this one is the "big one". It's got the 8800M GTX SLI.
Story goes like this. He found it for a good price and bought it to part it out. All the lights went on but no video.
Someone from a different town got interested in the motherboard. The motherboard was sold. It came back as not working... And it didn't work indeed. Now it turned on for a few seconds and then turned off. Only the power LED lit up, and the keyboard backlight gave a brief flash. If turned on holding the Fn key down (diagnostics mode), it displayed the "no CPU" code on the num/caps/scroll leds.
Everything had power, so i suspected the BIOS. Indeed, the BIOS chip was completely fried, so i programmed another one and soldered it in. I asked my friend whether he disassembled the laptop on a blanket and he said yes... Something he shouldn't do in the future.
After replacing the BIOS chip, it now showed some more signs of life, with the board flashing the appropriate codes when the CPU, GPU or RAM were removed. But the other lights still didn't come on, and it still shut down after a few seconds.
The guy who sent it back said he tried a lot of different CPUs and RAM and the board still didn't work (with the BIOS chip fried entirely, no small wonder). On this board, the Northbridge is located right above the RAM slots, and this being an odd-shaped board, the NB is quite close to the edge. My nose said that NB had unsoldered due to flexing. My nose was right... One reflow later, we have all the lights coming on. Yay.
Of course, that left the original issue - no video. So my attention went to the video card. The board had been messed around with and is kinda discolored. But the only chip that had its epoxy removed (but it wasn't actually reballed, as i found out later), was the SLI bridge chip. The GPUs didn't look like they were touched. I reflowed all three to make sure, but still no go.
Now, this has the 8800M GTX which is G92-720-A2. This chip shouldn't be defective, right? The datecode of the GPUs is 2010 - by that time, nVidia had already gotten their act together, so why would they fail... This card had likely been replaced at least once under warranty, the GPUs are just too new.
But there is one other chip on the board, and that's that little bugger of a SLI bridge.... and guess the datecode on it... beginning of 2008. Bingo. I took the bridge chip off, cleaned it, and gave it some "special treatment" before reballing it and putting it back on. "Special treatment" means covering everything but the die, and getting the die really, really hot. This does seem to bring some chips back from the dead, at least for long enough for you to be 100% sure of the fault.
Put it back on, re-installed the card, hit the power button, and.... "DELL" said the screen.
It worked for long enough for me to be able to get in the BIOS and look at some stuff. It seems that both GPUs are initialized, as it reports video memory as 1024MB. The 8800M GTX SLI has 512MB for each GPU. Screen stopped responding a couple minutes later. Turned off and back on it works for shorter and shorter periods of time, until it doesn't display anything again, and needs to be left turned off for a while.
So the bad news? The bridge chip is buggered. The good news? It's dirt cheap. http://www.ebay.com/itm/Brand-New-NV...item2a1c85410a
Guess nVidia had some old stock left they wanted to monetize. So hey, why not sell it to Dell? Shame on them, this would have been a reliable GPU otherwise. But this also means that i'm getting a laptop that is powerful even by nowadays standards, for peanuts.
Yes, i may get to keep this beast.
Story goes like this. He found it for a good price and bought it to part it out. All the lights went on but no video.
Someone from a different town got interested in the motherboard. The motherboard was sold. It came back as not working... And it didn't work indeed. Now it turned on for a few seconds and then turned off. Only the power LED lit up, and the keyboard backlight gave a brief flash. If turned on holding the Fn key down (diagnostics mode), it displayed the "no CPU" code on the num/caps/scroll leds.
Everything had power, so i suspected the BIOS. Indeed, the BIOS chip was completely fried, so i programmed another one and soldered it in. I asked my friend whether he disassembled the laptop on a blanket and he said yes... Something he shouldn't do in the future.
After replacing the BIOS chip, it now showed some more signs of life, with the board flashing the appropriate codes when the CPU, GPU or RAM were removed. But the other lights still didn't come on, and it still shut down after a few seconds.
The guy who sent it back said he tried a lot of different CPUs and RAM and the board still didn't work (with the BIOS chip fried entirely, no small wonder). On this board, the Northbridge is located right above the RAM slots, and this being an odd-shaped board, the NB is quite close to the edge. My nose said that NB had unsoldered due to flexing. My nose was right... One reflow later, we have all the lights coming on. Yay.
Of course, that left the original issue - no video. So my attention went to the video card. The board had been messed around with and is kinda discolored. But the only chip that had its epoxy removed (but it wasn't actually reballed, as i found out later), was the SLI bridge chip. The GPUs didn't look like they were touched. I reflowed all three to make sure, but still no go.
Now, this has the 8800M GTX which is G92-720-A2. This chip shouldn't be defective, right? The datecode of the GPUs is 2010 - by that time, nVidia had already gotten their act together, so why would they fail... This card had likely been replaced at least once under warranty, the GPUs are just too new.
But there is one other chip on the board, and that's that little bugger of a SLI bridge.... and guess the datecode on it... beginning of 2008. Bingo. I took the bridge chip off, cleaned it, and gave it some "special treatment" before reballing it and putting it back on. "Special treatment" means covering everything but the die, and getting the die really, really hot. This does seem to bring some chips back from the dead, at least for long enough for you to be 100% sure of the fault.
Put it back on, re-installed the card, hit the power button, and.... "DELL" said the screen.
It worked for long enough for me to be able to get in the BIOS and look at some stuff. It seems that both GPUs are initialized, as it reports video memory as 1024MB. The 8800M GTX SLI has 512MB for each GPU. Screen stopped responding a couple minutes later. Turned off and back on it works for shorter and shorter periods of time, until it doesn't display anything again, and needs to be left turned off for a while.So the bad news? The bridge chip is buggered. The good news? It's dirt cheap.
http://www.ebay.com/itm/Brand-New-NV...item2a1c85410aGuess nVidia had some old stock left they wanted to monetize. So hey, why not sell it to Dell? Shame on them, this would have been a reliable GPU otherwise. But this also means that i'm getting a laptop that is powerful even by nowadays standards, for peanuts.
Yes, i may get to keep this beast.
You can also buy some epoxy remover, but that one didn't prove to do its job...Only using it on iPhones+hot air, cause that black stuff is really hardcore...
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