Thinkpads Forum

I am looking to buy a working processor for a Thinkpad R52. The socket is the MPGA479M. I would like to buy either a pentium or if possible a centrino.

Thanks
Brandon

Just wanted to point this out to you:

Pentium M is the actual processor

Centrino is Intel's name for their portable platform. For a system to be considered a Centrino system, it must have a mobile Intel processor, an Intel 802.11a/b/g/n (any of those) card, and an Intel chipset.

Correct me if I'm wrong.

I believe that is correct but the actual processor that goes with the centrino setup has the 2048 Level 2 Cache as the pentium only has the 512 or the 1024. All of which are better than my celeron with the 256. lol

Thanks
Brandon

If you are looking for a processor with a 2MB L2 cache, you're looking for Dothan core Pentium Ms. Banias core Pentium Ms were manufactured on a 130nm process (as opposed to 90nm for Dothan) and have only 1MB L2.

Ok I am looking for a Pentium over 1.4 that will fit in my socket. lol

Not only would you want to get a Pentium M Dothan, but it would have to be of the 533Mhz FSB variety to run on an R52.

See this link for Intel part numbers -

http://en.wikipedia.org/wiki/List_of_In ... processors

For example, if you were looking for a 2.0GHz 533MHz Pentium M 760, the part is SL7SM. If you use EBay, you'd search for SL7SM. $80 is @ the going price for that part used. Personally I've done a 1.86 to a 2.0 Dothan upgrade on an R52, but have never done a Celeron to Pentium M Dothan upgrade. I assume it would work, but I'm not 100% positive.

Harryc wrote:Not only would you want to get a Pentium M Dothan, but it would have to be of the 533Mhz FSB variety to run on an R52.

I don't think it has to be 533, they are compatible with 400 too iirc.

aaa wrote:I don't think it has to be 533, they are compatible with 400 too iirc.

Not true, yes a 400Mhz will run but not at full speed. An R52 is functionally equivalent to a T43 which also takes 533MHz CPU's. I had one, I definitely know what CPU's it takes ...

Harryc wrote:

aaa wrote:I don't think it has to be 533, they are compatible with 400 too iirc.

Not true, yes a 400Mhz will run but not at full speed.

But with the pin mod it can be overclocked giving a 33% of increase in speed.

Harryc wrote:

aaa wrote:I don't think it has to be 533, they are compatible with 400 too iirc.

Not true, yes a 400Mhz will run but not at full speed. An R52 is functionally equivalent to a T43 which also takes 533MHz CPU's. I had one, I definitely know what CPU's it takes ...

R52 1958-3LU is 400mhz. Apparently the BIOS supported cpus are different on the R series.

cmarti wrote: But with the pin mod it can be overclocked giving a 33% of increase in speed.

Definitely something 90base should research. It's tricky to do, but you can turn a cheap 1.6/400 into a 2.1/533 that way.

90base wrote:I am looking to buy a working processor for a Thinkpad R52. The socket is the MPGA479M. I would like to buy either a pentium or if possible a centrino.

Thanks
Brandon

Thinkpad R52 1858-CTO
1.24GB or Ram
80GB Fujitsu Hard Drive
Intel Celeron 1.4 (looking to buy centrino)
Windows XP Pro SP2 Build 2600
128 MB Video

Judging by the information you provided, you have a Celeron based R52 and would like to make it Pentium M based.

Your Celeron CPU bus speed is currently running at 400MHz. You also happen to most likely have the R52 motherboard that is based on the 910GML chipset. This is the entry level board for R52's, more than one chipset option was available. This is the default motherboard that IBM provided with the Celeron based R52's (Intel 915GM and 915PM based boards were used for the Pentium M based R52's.)

The 910GML chipset was designed specifically for 400MHz Celeron CPU's, see this link --> http://www.intel.com/products/chipsets/910gml/index.htm

It does not officially support Pentium M cpu's of either bus speed 400MHz or 533MHz.

However, I have done some testing with a 910GML based R52 and I can tell you that 400MHz Pentium M cpu's up to 1.6GHz work fine (I only tested Dothan 1.5GHz and 1.6GHz cpu's.) I can also tell you that I had trouble with both 1.86GHz and 2.0GHz 533MHz-bus Pentium M cpu's. The BIOS correctly identified the CPU, but the R52 would shut down after 30 to 90 seconds.

So, for a stable upgrade and to increase speed a little and increase battery life, I recommend that you pick up a 1.6GHz Pentium M Dothan cpu. I say Dothan because the Celeron you are currently using is based on the Dothan architecture (Banias may not work). I believe these sell for as little as $25.

Of course, you could try for a faster Dothan Pentium M (400MHz bus) as well.

P.S. Everybody (including myself) seem like experts that express authoritative comments, you have to sift through all the details and decide for yourself on what to do.

Since I bought my first R52 from Ed, I'll defer to his expertise. I didn't even realize they came in a Celeron version. I've learned something new today ... to the OP, ignore my advice . I must be one of those who " seem like experts that express authoritative comments". LOL.

underclocker wrote:P.S. Everybody (including myself) seem like experts that express authoritative comments, you have to sift through all the details and decide for yourself on what to do.

Actually, this statement wasn't meant to be targeted. It's true everywhere, from an automobile showroom to the doctor's office. You've got to read between the lines and do a little research on your own for the best results...in general!

I agree about the 'sift through all the details and decide for yourself' part. Good advice 'in general'.

So what you are saying is the fastest that I can safely go is 1.6 Pentium M Dothan. And that is with the 400 or the 533?
Thanks
Brandon

p.s. I just want everything to be clear before i waste money I dont have on something that wont work

I would try a Pentium M 1.6GHz Dothan 400MHz processor. In particular, this one, SL7EG, which is also called a Pentium M 725.

Just search eBay or Google for SL7EG.

I would not try the Pentium M 725A. You can search for more information about the 725A on this site.

P.S. This is advice, it comes with no warranty/guarantee!

P.P.S. Best case scenario, for $25 it works. Worst case scenario, you do something wrong and destroy your motherboard...well, I suppose it could get worse, you could catch your house on fire with some kind of short circuit...they're your dice, roll them as you wish...

I have a Banias 1.4GHz 400FSB CPU I have no use for. PM me if you are interested can sell it for $30 shipped.