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For those who might want to contribute to the blog, start here: Editors Alley Topic
Then contact Bill with a Private Message
T21 upgrades
T21 upgrades
Hello! I just bought a T21, specs are 800MHZ, 256MB, 20GB HDD, DVD, and XP SP3. From what I read on the forums, some upgrades include memory and CPU. Are there any other things that can be done to increase performance?
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rkawakami
- Admin Emeritus

- Posts: 10327
- Joined: Sun Jun 04, 2006 1:26 am
- Location: San Jose, CA 95120 USA
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Re: T21 upgrades
Welcome to thinkpads.com!
The T21 can go up to 512MB, using two 256MB PC100 or PC133 "low-density" memory modules (ones using 16 memory chips). With XP SP3, that's pretty much a must have. The other upgrade would be to a faster disk drive, assuming that your system has an older 4200RPM version. Any PATA (Parallel ATA) / IDE / EIDE drive will work; SATA (Serial ATA) will NOT. The fastest CPU that originally came with the T21 is 850Mhz. I believe that it's possible to get a 1Ghz PIII CPU to work in there, but don't quote me. I'm sure that somebody around here has the correct answer or it can be found by searching the archives. However, even with that small of a boost (~18%) I doubt that you would notice that much of a difference with typical browsing or office tasks. You may also have to upgrade the heatsink/fan assembly to handle the higher temperatures that would be emitted. Use Google to search for tips on streamlining XP; turn off all of the "eye candy" features and keep background programs to a minimum. Check the Power Manager and System Properties/Advanced tabs for quick and easy things to change (i.e., "maximum performance" or "best performance" settings). Make sure you defrag the disk every couple of weeks. Consider using a different antivirus solution if you think that it's dragging the system to its knees.
What do you see as the main use for "new" T21?
ref: http://forums.thinkpads.com/viewtopic.php?f=5&t=17552 (did the search: T21 Processor upgrade)
The T21 can go up to 512MB, using two 256MB PC100 or PC133 "low-density" memory modules (ones using 16 memory chips). With XP SP3, that's pretty much a must have. The other upgrade would be to a faster disk drive, assuming that your system has an older 4200RPM version. Any PATA (Parallel ATA) / IDE / EIDE drive will work; SATA (Serial ATA) will NOT. The fastest CPU that originally came with the T21 is 850Mhz. I believe that it's possible to get a 1Ghz PIII CPU to work in there, but don't quote me. I'm sure that somebody around here has the correct answer or it can be found by searching the archives. However, even with that small of a boost (~18%) I doubt that you would notice that much of a difference with typical browsing or office tasks. You may also have to upgrade the heatsink/fan assembly to handle the higher temperatures that would be emitted. Use Google to search for tips on streamlining XP; turn off all of the "eye candy" features and keep background programs to a minimum. Check the Power Manager and System Properties/Advanced tabs for quick and easy things to change (i.e., "maximum performance" or "best performance" settings). Make sure you defrag the disk every couple of weeks. Consider using a different antivirus solution if you think that it's dragging the system to its knees.
What do you see as the main use for "new" T21?
ref: http://forums.thinkpads.com/viewtopic.php?f=5&t=17552 (did the search: T21 Processor upgrade)
Ray Kawakami
X22 X24 X31 X41 X41T X60 X60s X61 X61s X200 X200s X300 X301 Z60m Z61t Z61p 560 560Z 600 600E 600X T21 T22 T23 T41 T60p T410 T420 T520 W500 W520 R50 A21p A22p A31 A31p
NOTE: All links to PC-Doctor software hosted by me are dead. Files removed 8/28/12 by manufacturer's demand.
X22 X24 X31 X41 X41T X60 X60s X61 X61s X200 X200s X300 X301 Z60m Z61t Z61p 560 560Z 600 600E 600X T21 T22 T23 T41 T60p T410 T420 T520 W500 W520 R50 A21p A22p A31 A31p
NOTE: All links to PC-Doctor software hosted by me are dead. Files removed 8/28/12 by manufacturer's demand.
Re: T21 upgrades
I use it for Web browsing, online automotive tech library, and eventually as an automotive scan tool.
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rkawakami
- Admin Emeritus

- Posts: 10327
- Joined: Sun Jun 04, 2006 1:26 am
- Location: San Jose, CA 95120 USA
- Contact:
Re: T21 upgrades
Well then, what I've outlined before should apply. The T21 does not natively support USB 2.0. The USB interface on the T21 (all of the T2x series in fact) uses the older 1.1 technology. If you absolutely need a 2.0 connection, you can use a PCMCIA-to-USB adapter. If your tech library is based in .PDF files, consider using an Adobe Reader compatible program like Foxit Reader. That program seems to need less system resources than a full-blown Adobe install.
Ray Kawakami
X22 X24 X31 X41 X41T X60 X60s X61 X61s X200 X200s X300 X301 Z60m Z61t Z61p 560 560Z 600 600E 600X T21 T22 T23 T41 T60p T410 T420 T520 W500 W520 R50 A21p A22p A31 A31p
NOTE: All links to PC-Doctor software hosted by me are dead. Files removed 8/28/12 by manufacturer's demand.
X22 X24 X31 X41 X41T X60 X60s X61 X61s X200 X200s X300 X301 Z60m Z61t Z61p 560 560Z 600 600E 600X T21 T22 T23 T41 T60p T410 T420 T520 W500 W520 R50 A21p A22p A31 A31p
NOTE: All links to PC-Doctor software hosted by me are dead. Files removed 8/28/12 by manufacturer's demand.
Re: T21 upgrades
Thanks for the advice! I just obtained a pcmcia to usb 2.0 card for the OBD II interface, and will be upgrading to 512MB soon. My tech "Library" is web based, so I'm good there.
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