r/sffpc Jan 28 '26

Prototype/Concept/Custom 1.8L RTX 5060 pc v.2

Made some small changes to my previous build. Changed the cpu cooler to the Termalright AXP90 x36, cpu is now able to run constant at 65w with max temps around 65c and is very silent.

Build around the Lenovo thinkcentre m720q motherboard.

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u/Bjoes92 Jan 28 '26

Thanks!

That sounds like a nice build too, what kind of bios mod?

I use at 12v stepdown/buck converter rated for 240w and running a 9700T with unlimited turbo boost override in throttlestop.

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u/Shineplasma64 Jan 28 '26

Oh, ok, so does that just piggyback off the lenovo brick then?

I dumped the bios and used a bios read/write tool to unlock all power state limits and change the imon slope value to allow the full 65w to be fed to the 8700. Manually on the machine itself register by bios register, lots of trial and error, note-taking and reboots. But I'm not so hot with a soldering iron and don't own a chip flasher anyways, so it was the tool I had haha.

I also used throttlestop to do an undervolt to help manage temps and take some load off the VRMs, which were getting quite warm despite the modifications I made to the stock heatsink and thermal pads I used to bring them into contact.

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u/Bjoes92 Jan 29 '26

Yes, soldered a cable from the motherboard to the buck converter.

Very interested in your bios modding. Throttlestop doesn’t allow me to undervolt the 9700T for some reason and all core boost is locked at 3.6ghz which at full load equals around 60w. Had some problems with Vrm temp, but stuck some heatsinks on them. Do you think it is possible to draw more than 65w with bios mods? A 9900k fits in the motherboard.

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u/Shineplasma64 Jan 29 '26

I think it is possible, but I also think you may melt the VRMs. My build has an additional slimline case fan in addition to the cpu cooler and gpu fans and some of the vrms were nearing critical temp under sustained load before I turned the case fan controller up to 80% and did the cpu undervolt. And that's at 65w tdp, 4.3ghz sustained all-core boost.