T21 Motherboard Replaced - Issues

[nikki605]

OK, so the persistant power problems didn't get fixed after trying to have the original mobo repaired! I finally broke down and bought a used mobo on ebay - $70 plus shipping. It came with the CPU, heatsink/fan, PC card slot frame, device bay frame and everything in the case bottom - none of which I used. I got it this afternoon and installed it. Basically, it works... so far. I'm typing this post on it. I'll have to run it several days or weeks to be sure. I was more worried that it would have its own, new problem.

The previous mobo made the unit a 2647-47U. This "new" board is a 2647-8AU. What's the difference? Naturally, it also displays different system and mobo serial numbers, but who cares. Its not like its still under warranty or something. Its 6 years old, I've upgraded the heck out of it, and I'm just trying to get a little more life out of it. The ebay seller offered a warranty from SquareTrade that I may just go ahead and buy. 2 years coverage (on used items) for $8.99. If it fails, I get my money back.

The only thing I did was to flash the BIOS to the latest version - KZET34WW (1.16). After doing this, I noticed that the layout and information in the BIOS setup screens was vastly different from the original mobo. Why are they different? Is there anything I should check or do in the "new" BIOS?

Everything seems to work. I had upgraded the CPU (and heatsink/fan) on the original mobo from 800MHz to 1GHz (thanks to information I found on this forum) and I put the 1GHz CPU on this mobo and it works fine. The BIOS recognized it and CPU-Z says its running at 995MHz (about the same speed as it ran on the original mobo). I put both memory sticks in and it recognized the 512MB total memory (the max for the T21). I tested both PC card slots, the DVD-ROM, floppy drive and the modem side of the modem/ethernet adapter (I only have a dial-up ISP). It even took right off and ran from the upgraded Hitachi 7K100 80GB HDD loaded with Win XP Pro that I had in the original unit.

I even ran a cycle of PC Doctor booted from CD (thanks for the link to the iso image). It ran without error.

The only unexpected thing was after one of several startup/shutdown cycles I did while installing software updates, Windows displayed a box that said something about significant hardware changes had been made (well, duh) and Windows needed to be re-activated. So I followed the prompts, it dialed out and re-activated without a problem.

In addition to my questions above, let me say that without the information I found on this forum, I don't think I would have attempted this replacement myself. You guys are great

Guess I'll have to change the model information in my sig to -8AU.

[rkawakami]

The previous mobo made the unit a 2647-47U. This "new" board is a 2647-8AU. What's the difference?

The basic difference is what operating system shipped with the system and networking capability. The 47U came with Windows 98 and no ethernet, while the 8AU had Windows 2000 and a combo modem/ethernet card.

Product: ThinkPad T21 2647-47U [change]
Operating system: All [change]
Original description: PIII 800MHz (256KB), 128MB RAM, 20.0GB HDD, 14.1 XGA(1024x768) TFT LCD, 8x-2.3x DVD, Modem, TV out, Li-Ion Battery, W98

Product: ThinkPad T21 2647-8AU [change]
Operating system: All [change]
Original description: PIII 800MHz (256KB), 128MB RAM, 20.0GB HDD, 14.1 XGA(1024x768) TFT LCD, 8x-2.3x DVD, Intel Combo, TV out, Li-Ion Battery, W2000

After doing this, I noticed that the layout and information in the BIOS setup screens was vastly different from the original mobo. Why are they different? Is there anything I should check or do in the "new" BIOS?

I have not flashed the BIOS on too many systems so I'm not sure what the changes are. You can read the revision history of the BIOS updates at:

ftp://ftp.software.ibm.com/pc/pccbbs/mo ... sukz34.txt (site currently having some problems)

I even ran a cycle of PC Doctor booted from CD (thanks for the link to the iso image). It ran without error.

If you got that off my site, then you're welcome. One of the sources for the .ISO went off-line a couple of months back so I put a copy up on my domain. If you really want to execise your laptop, put PC Doctor into a looping mode (press the F2 key and change the "Set Pass Count" value) and it will repeat your selected tests that many times.

<snip>... Windows needed to be re-activated. So I followed the prompts, it dialed out and re-activated without a problem.

I believe that the retail version of Windows (perhaps along with Windows Genuine Advantage) will detect major modifications to the hardware setup and "phone home" for re-activation. It's the MS way of trying to deal with software piracy. I seem to have read that a memory change alone should NOT trigger the re-activation cycle, but that happened to me a year ago.

[nikki605]

I think I did get the PC Doctor .iso image from your web site, Ray, so thanks again.

The label on the bottom of the baseplate did say Windows 2000 (8AU) and my system originally came with Windows 98 (47U) as you said.

Since the replacement mobo had all of the plugin modules removed, I just moved the 3Com modem/ethernet mini PCI card into the new mobo. I just need to get to a high speed internet connection to test it, but I expect it will work.

Both boards now have the same BIOS version installed (1.16), so that is the same. What is different is the layout and organization of the screens when I enter the BIOS setup utility when booting. It doesn't appear to be a problem, just strange to look at. But, since its working, I won't need to look at it very often. The only change I had to make in the BIOS was the device boot sequence. Floppy first, then CD, then HDD. It was set to something else (don't remember what) after I flashed it.

I only had time to run the new mobo for a few hours last night after getting it put back together, but I did notice one immediate difference. With the original mobo (even after having the MOSFETs replaced which fixed the power problem but only for a few weeks) I noticed that the area of the left palm rest would get very warm, almost hot, to the touch. Both top and bottom of the laptop, but the bottom was way hotter. This is in the area of the HDD, memory sticks, the 3 audio connectors, and the infrared port. I had upgraded the HDD several months ago and since it was still getting hot, I didn't think it was the HDD itself. Besides, MobileMeter measured the temp within normal limits. With the same, upgraded 80GB HDD installed on the replacement mobo, and also the same 2 - 256MB memory sticks installed, this mobo got nowhere near as hot. I'm looking at the old mobo right now and there are many components in that area on the top side of the mobo, under the HDD frame, and also on the bottom side of the mobo, under the memory sticks. I cannot see any obvious signs of physical damage, so I don't know which component was getting so hot.

Only time will tell if this fixes my powering off problem (without introducing a new problem) but I have renewed hope for my aging T21. My thanks again to everyone who has contributed to this forum and provided such a wealth of information. In my opinion, this is one of the best user forums I've come across!

Anybody want a bad mobo?