You can install a quadcore. 2720QM is been tested working. http://forum.notebookreview.com/threads/t420-upgrade-to-i7-2720qm-es-q154-su...
The probably fastest CPU that the T420 could get cooled is the Core i7-2860QM (45W TDP).
Official dualcore CPUs have a TDP of 35W. Those inofficial working quadcore CPUs have a TDP of 45W. The minimal requirement to get those quadcore CPUs working is to apply the very best thermal paste you can get for money. At the moment this is the "Thermal Grizzly Kryonaut". Otherwise your CPU would start overheating and throttling when you use for example a old and inefficient Arctic Silver 5.
Untested/unknown: If a ivy bridge CPU would work. The OEM bios didn't had support for those.
5. Feb 2017 18:33 by davidthornes at outlook.com :
Hello All, I have a question for people running coreboot on T420Can you please suggest the fastest CPU i can upgrade to without too many heat issues ?i can use more powerful ( 90W i think ) power brick if needed ..thank you everyone.David.
Hi
Untested/unknown: If a ivy bridge CPU would work. The OEM bios didn't had support for those.
Ivy Bridge works, have a 3740QM in mine. However, (quoting myself here):
I'm running one albeit with an i7-3740qm - which is too much thermal load, runs up to 2.9 GHz for me reaching 93°C (70K to ambient) with fan set to disengaged, normal auto fan control works and allows up to 2.5 GHz.
with that CPU RAPL does not work, thermald does but out-of-the-box settings gives me less performance than with fix limits, and I'm sure as hell not going to configure something with an xml config file.
used to have a 2720m which worked without any issues AFAIR, but the 3740qm effectively gives me double the cores that are a little faster.
Regards, Arian
Could you try out "Thermal Grizzly Kryonaut" or even liquid metal based products and report about the temperatures? It would be great if you could try out first the Thermal Grizzly Kryonaut and later then for example the Thermal Grizzly Conductonaut and report here. http://www.overclock.net/t/1588116/thermal-grizzly-conductonaut-73-w-mk
Please clean up the surface before applying when possible with https://en.wikipedia.org/wiki/Isopropyl_alcohol (its cheap and easy to get).
23. Feb 2017 01:28 by coreboot@semioptimal.net:
Hi
Untested/unknown: If a ivy bridge CPU would work. The OEM bios didn't had support for those.
Ivy Bridge works, have a 3740QM in mine. However, (quoting myself here):
I'm running one albeit with an i7-3740qm - which is too much thermal load, runs up to 2.9 GHz for me reaching 93°C (70K to ambient) with fan set to disengaged, normal auto fan control works and allows up to 2.5 GHz.
with that CPU RAPL does not work, thermald does but out-of-the-box settings gives me less performance than with fix limits, and I'm sure as hell not going to configure something with an xml config file.
used to have a 2720m which worked without any issues AFAIR, but the 3740qm effectively gives me double the cores that are a little faster.
Regards, Arian
Actually there is an even better non-conductive thermal paste (not liquid metal) than "Grizzly" --- it is called " Gelid GC-Extreme ". Here is a comparison from one review website that I screenshotted - https://s4.postimg.org/qvp326pjx/Thermal_Grease.png . The difference between them is not big, but I think in your case every degree counts. Also, there is a packaging of Gelid GC-Extreme that is 10g - http://gelidsolutions.com/thermal-solutions/thermal-compound-gc-extreme-10g/ , this larger packaging gives a very affordable price per 1g and will last for a long time ;)
2017-02-23 4:49 GMT+03:00 i1w5d7gf38keg@tutanota.com:
Could you try out "Thermal Grizzly Kryonaut" or even liquid metal based products and report about the temperatures? It would be great if you could try out first the Thermal Grizzly Kryonaut and later then for example the Thermal Grizzly Conductonaut and report here. http://www.overclock.net/t/1588116/thermal-grizzly-conductonaut-73-w-mk
Please clean up the surface before applying when possible with https://en.wikipedia.org/wiki/Isopropyl_alcohol (its cheap and easy to get).
- Feb 2017 01:28 by coreboot@semioptimal.net:
Hi
Untested/unknown: If a ivy bridge CPU would work. The OEM bios didn't had support for those.
Ivy Bridge works, have a 3740QM in mine. However, (quoting myself here):
I'm running one albeit with an i7-3740qm - which is too much thermal load, runs up to 2.9 GHz for me reaching 93°C (70K to ambient) with fan set to disengaged, normal auto fan control works and allows up to 2.5 GHz.
with that CPU RAPL does not work, thermald does but out-of-the-box settings gives me less performance than with fix limits, and I'm sure as hell not going to configure something with an xml config file.
used to have a 2720m which worked without any issues AFAIR, but the 3740qm effectively gives me double the cores that are a little faster.
Regards, Arian
-- coreboot mailing list: coreboot@coreboot.org https://www.coreboot.org/mailman/listinfo/coreboot