Thinkpads Forum

Hello,
I just had to replace the fan in my T420s, which luckily I replaced once before and I had an older one sitting around that still works. I want to buy another one and I noticed there seems to be no new fans that are from lenovo anymore, or the few that are around $70 each. A little harder to find is the version with the nvidia graphics, which mine has. I did notice that the T430s fan looks very similar, and I was wondering if that would work in the T420s. I also saw that people were using the T430 fans in the T420, but I know this doesn't mean that it applies to the s models. Is there anywhere that these fans are easy to get and not over priced?
Is there maybe any other upgrades? I wouldn't mind having a more powerful cooling system, and noise isn't a concern. After replacement I realized my old fan has been very noisy for a long time now.
My last question will be if there is any way to oil these fans? It doesn't seem like you have access under the fan blades, and it is just sealed.

If you are a DIYer, on many heatsinks you can just replace the fan itself (even if it is a slightly different model or make).
See this for your model: https://www.ebay.ie/itm/183998411166

Thank you, I completely missed that option because I was rushing and only was checking parts that was coming from North America.
Something I want to confirm is if the fans are the same between the 04W0416 / 04W1712 (integrated graphics) and 04W0417 / 04W1713 (dedicated graphics)? They look similar enough in all ways except the non s is missing one heat pipe.

On ebay, I found a fan/heatshink that was labeled for a T430s, which looks like it will fit into my T420s.
I will give it a try some day, but I figured the worst case was to use the fan from it. The part number is 04W3487, which is for the models with graphics cards. Looking through the T430s fans, it looks like some have 3 wire fans and others have 4 wires, or maybe the T430s has 3 wires and the T430 has 4. I didn't go deep enough to figure this out.

Get the 4 pin ones (they have PWM modulation, I think). The others are to be avoided like the plague.

BTW: What were your temperatures when the fan was working? Did your T420s overheat?

I can't go from a 3 pin to 4 pin as the motherboard only has 3 pins.
In more recent years, my T420s was getting too hot, but since replacing the fan, the temperatures dropped a lot. I wouldn't be surprised if that fan was going bad for years anyway, this laptop spends 90% of its life, turned on and the fan at at least 50%. Right now, my temperature is in the mid 60s C, with watching videos. I have to be careful not to push the video card too hard, I don't think the heat sink is making great contact with the video card.

From my investigation, it's a widespread issue: many models of that era have problems with ASPM. Some because of buggy drivers or BIOSes, some because hardware itself is buggy. Thing is, many manufacturers (including Lenovo) decided that the best way to deal with the issue was to ignore it; and thus disabled ASPM entirely. With ASPM disabled you can expect the system to draw many more watts and produce more heat as a result.

The T420s in particular came with a problematic card reader (Ricoh). It seems like the driver hangs trying to read some configuration files from the card. Get rid of it if you can, and your machine will run cooler.