I just got my hands on a Thinkpad T61p, and it's been a pleasure using it so far. Since I use an SSD I installed the Middleton BIOS (which works like a charm), and I also found out that it would allow me to upgrade my Merom based T7500 2,2GHz to a Penryn CPU. I've looking into buying a T9300 2,5 GHz on ebay, which will be around 60-70$.

Is this upgrade worth the time and money? Will there be any noticeable improvements when it comes to pure performance and temperatures?

Grateful for any replies and suggestions!

Looking at the numbers, it's not really a big difference between the two processors. They both have the exact same capabilities, it's just a die shrink and a speed bump - guessing around 30-35% faster. If I had a T7300 already, I wouldn't do it, but if you need the extra speed, go for it.

How much of an impact does the amount of L2 cache have? My current T7500 has 4mb, while the T9300 has 6mb. I've also heard that the Penryn CPUs run much cooler compared to Merom. Although undervolting is always an option.

Only when you're maxing the CPU will you notice any difference and even then it will be very small. If it's just for every day stuff, I'd pass.

Penryns do run both cooler and faster.

If you really love that T61p and have maxed out all the other options, go for it...or a X9000...if you've got money to burn, that is...

I mainly browse the web and watch videos on it so far, I play some games at times though but I'm satisfied with the performance (Starcraft 2 1920x1200 Low Settings average fps ~ 60fps).

ajkula: How much cooler will it run?

Also would upgrading memory to a total of 8gb of ram be something to consider? 4gb SO-DIMM DDR2 sticks are quite pricey here in Sweden.

For what you've said you do, 4 GB would be plenty to get that laptop through to retirement IMHO

You're likely to get 5-10 degrees C cooler machine on idle.

But overall, even if you were to go to T8100/8300 which are a lot cheaper than T9300 you'd see better temperatures with no loss in performance.

That sounds like a major improvement to me, especially since the cpu shares the same heatsink with the gpu. I guess what I'll do is to try and undervolt my CPU and see how much the temperatures will drop as a result of that.

EDIT: Any recommendations of where I should buy, don't really want to spend more than 100$. Are these "top-rated" ebay sellers any reliable regarding the product descriptions?

Once again thanks for the help!

The failure rate for CPUs is extremely low. It's likely to work or not, but unlikely to fail down the road. I'd buy on price. If it doesn't work you can always dispute it.

I have to disagree on the "buy by price" theory regarding CPUs. We're talking about the most important part of your computer and I'm often shocked when I see people obsessing over something as meaningless as a shiny spot on a keyboard, which is really of no importance at all with the function of the computer, then assigning the same value to a low milage mint cpu as you would to one pulled form a laptop that is dead, smashed, or even fried in electrical fire, or in the case of a high end cpu, one that has likely been overclocked and overheated dozens if not hundreds of times.

I've had opportunities to sort through corporate laptops to pick out the best of the best before anyone got to them, usually looking for units to source for rare system boards and other parts, but if you've seen what I have, you'd be very careful buying a cpu from someone you don't trust. When a shipment of hundreds of laptops comes in, the ones that I don't select for myself are auctioned to brokers who then list the laptops for sale on various websites including ebay and others. With every "lot" there are always a number of units that even the cheapest of the brokers won't touch. These are loaded onto pallets and shipped to Asia where part stripping factories, employing child labor strip out all the parts, usually untested and sell them. Most of your low priced CPUs come from these, some of which are computers that have been in electrical fires, smashed so badly that they're in many pieces, and some are just dead, for various reasons.

Keep in mind that the people who sell these parts are motivated only by profit. They don't waste time testing them, they leave that upto the buyer. When one is bad, they offer a replacement and most buyers are understanding and are only concerned with getting a refund or replacement and usually leave favorable feedback even if they get a bad one the first time... but it's far cheaper to ship a couple extra units then to do testing of each component beforehand.

Granted that it's very possible to pull a cpu from one of these and have it work... even from a unit that was in an electrical fire, but if I was buying a CPU and had a choice of an unknown CPU for $50, or one pulled from a mint condition unit that is fully functioning for $100, I'd choose the latter... and the really ironic part is the price difference is rarely that vast.


My opinion is you use at least the same care when buying a cpu as buying a keyboard or display... no one here would buy a display without asking questions about it's condition. If you have a seller you trust that has personally tested a computer before pulling a chip, then I'd assign a premium value to that chip as compared to an unknown chip from an unknown seller. I often purchase corporate laptops to fill orders for rare system boards. In testing, these machines are run for several days to make sure the boards are good, then in most cases things like the CPU's are sold later, or used in custom builds. I would never buy the cheapest chips I could find. Even if they do work, I'd still not trust them to perform upto spec. These chips are so complex and some develop things like hotspots within them, and some develop thermal issues that aren't easy to demonstrate, but could cause problems that are very difficult to track down. It's also possible you're buying someone else problem. High end chips that have been extensively overclocked can develop thermal problems, then get dumped on ebay when the person upgrades to a better model.

Sorry for being "long winded", and I'll just sum it up by saying... be careful. Certain parts are ok to buy by price alone, but definitely not a system board or a CPU.

Thanks for the tips TuuS!

I'm still pondering over doing a cpu upgrade, although I'm not sure whether it should be a T8300 or T9300. I'm satisfied with the performance of the T7500, so what I would prioritize is improvements in heat and battery life. I feel like the T8300 is the better choice as it has lower clock speed and L2 memory compared to T9300.

Any recommendations on trustworthy sellers?

The coolest running chip with the lowest draw in the penryn class would be the T8100, at least when limited to the models that were optional in the T61 series. I recently built a T61 with a T8100 and a T61p fan and it ran so cool that the fan wouldn't even come on unless I ran something to give the cpu a workout. Compared to the T7500, it has less cache and slightly slower speed, but I still suspect performance would be about the same. The T8300 would give you better performance and efficiency. A T9xxx series chip would be best if you want performance, but they definitely can generate some heat.

I could probably get you any of these at prices similar to what they sell for on ebay if you're interested, but as far as recommending any one ebay seller, most that sell large amounts of cpus don't really care where they come from, and I don't know of any that sell only chips pulled from complete working units.

I did a little copy and pasting from the notebookcheck.net benchmarklist and made a selection so you can compare the performance of T61's processors. For comparison with the T60, I also added the T7600.
(image is 44kb so I think a direct show won't be a problem)


update: I decided to update the picture with (almost) all T60 and T61 cpu's so you can compare them all. Maybe this picture can be placed in some kind of FAQ?