Will this 1GHz CPU work in T20 ?

[aditya1956]

Hi everybody,

I am getting a Pentium III M 1 GHz CPU with the following specs., which I want to use in my T20. But I am not sure whether it will work or not. Knowledgeble members may help me out.

The specs are:

"SL53S (Intel Mobile Pentium III) Processor type Intel Mobile Pentium III Processor core Coppermine Part number BXM80526B001256 Package type 495-pin micro-PGA2 Processor speed (MHz) 1000/700 Bus speed (MHz) 100 L2 cache size (KB) 256 Core voltage (V) 1.7/1.35 Product stepping PD0 CPUID 068Ah Junction temperature (°C) 100 Notes on sSpec SL53S: The processor includes Intel SpeedStep technology. If more than one value is provided for the Processor speed and Core voltage fields then the first value is for maximum performance mode, the second value is for battery optimized mode."

As per me it should work alright. The pin/socket etc seems to be ok. But the voltage specs seem to be different. My 700MHz CPU is of 1.6/1.35 V, and this one is of 1.7/1.35 V. Well I don't know whether it will be a problem or not. I would like to be confirmed.

Also, I would like to know about the EXTRA HEAT issue, as I will have to use it only with the present T20_heatsink. I do not have access to one of the T21/22 types.

Thanks in advance

[Timoti]

The SL53S should work fine in a T20.

I use a SL5TF with a T21 heatsink/fan in my T20, and it has a smaller thermal tolerance (92 C) than the SL53S (100 C). Under heavy use, it can reach 92 C in a 22 C room, so i'd recommend using at least a T21 fan.

[nikki605]

The SL53S is what I installed in my T21 and it works fine. The T20 & T21 use the same motherboard so you should be fine.

The only other upgrade I did (recommended by other forum members here) was to install a T22 heatsink/fan assembly, FRU 26P9317. It is better at keeping a 1Ghz CPU cooler since it was designed for the 1Ghz, T22. It fits fine in the T21 and I would assume in the T20. I had to trim a small corner off of the CRU Insulator with a pair of scissors so it wouldn't rest on the larger T22 heatsink.

[aditya1956]

I am happy to hear that I can upgrade my favourite T20 now to 1 GHz.

The sad news is that I do not have the access to a 21_fan, at least not at the moment. I use this laptop only for email and web browsing. I hope the heat issues will be within the safe limits as there is no heavy usage. My present 700MHz cpu stays around 50C to 60C. I hope it will be within 70C if I use some good thermal compound between the heatsink & the cpu. My present compound is the old grey_thing, just repositioned and reused. A good thermal bond will probabely gain around 5/10C.

Thanks again

[nikki605]

I would suggest installing the Mobile Meter program to monitor the CPU temp. You can download it here

You can run it now before doing the CPU upgrade to get an idea of the current temp range. Then, after installing the 1Ghz CPU, run it again to see how much of a difference there is. Depending on how you use your T20, you may be OK.

Also, I applied Artic Silver 5 thermal compound to get the best possible heat transfer between the CPU & the heatsink. At complete idle, Mobile Meter measures my temp at 40C.

[tom_k]

@aditya1956

i strongly advise NOT to remove the "old grey thing" aka thermal rubber, but to reapply it in exactly the original position
The T20 fan is not designed to have direct contact with the die and leave a "big" gap,
even AS5 will not work as good as the rubber (dont`t add thermal grease to the rubber !)

I have/had several T2 of my own and for repair or upgrade
and would never use the 1GHz cpu with the "thermal rubber T20 fan",
even the T21 fan is in my opinion not massive/effective enough to transport the heat if you constantly "chase" the cpu.
I think you need the one which was used in T22 from 900MHz on.
see also:
http://www-307.ibm.com/pc/support/site. ... UYKLK.html
according to that site you need 26P9317,
it was produced in two different Versions,
the one i would prefer has a copper(CU) plate mounted downside covering the aluminium body,
the other version has a chromium(CR) plate.

tom_k

p.s.
i estimate after hours idling the 1GHz can go up to 70°C with rubber, and above 75 with lot of AS5.
26P9317 with chromium plate and little AS5 ( less is more! ;)
cuts it down to 40-48 °C in my 2647-9EG

[aditya1956]

i strongly advise NOT to remove the "old grey thing" aka thermal rubber, but to reapply it in exactly the original position
The T20 fan is not designed to have direct contact with the die and leave a "big" gap,

Many thanks for the concern shown.

Yes, I am aware of all these. Infact in this forum itself I had mentioned the same thing to another member in an earlier topic.

Actually many do not know this and throw the thermal rubber away. My plan was to use a new one as these are not as good once peeled off, though at the moment I am using the old one only. An original Intel thermal rubber is available here at my place readily. I had also asked for an IBM one but it is out of stock right now. I don't think it will be any different from the Intel one.

Yes, I am also equally worried about the heat factor in the absence of a superior heatsink/fan assembly. But as my use is nothing more than emailing and browsing, I hope it to be within 70C. Otherwise I will have to revert back to the 700MHz cpu and wait for a proper heatsink/fan thing to come.

Thanks again for the concern shown.