[DJ_Izumi]

I registered on this forum just to ask you about your system and experiences with it and different CPUs, TDP, throttling, etc. I have three of these Lenovo Tiny systems, one M93p and two M73's. If you're not familiar with the M73 version, it's almost identical to the M93p except it has an H81 chipset instead of the Q87 in the M93p, and some of the USB ports are only USB 2.0, otherwise they're identical. I currently have an i7 4770S in the M73 and while it boots up and runs fine, I've been concerned about it drawing too much power through the motherboard and eventually causing the board to fail. The 4770S is a 65W TDP CPU while the system was only designed for a 45W TDP CPU, and while TDP refers to maximum heat production/dissipation, in order to produce more heat you have to draw more power, which is my main concern.

Then I read this post where you mentioned above about there possibly being a power limit in the BIOS. I also happened to find your post on Reddit (it has the same keywords) where you said you had an i5 4590 (which has double the TDP!) in your M93 and the system engaged current throttling. How long did you have the 4590 in it and could you elaborate a bit about how and when you observed the current throttling with that CPU and your current one? Also, you mentioned that you managed to undervolt your current CPU. How did you do that? I didn't see any voltage settings in the BIOS on any of my Lenovo systems. 

I'm not concerned about heat because I'll be using that particular M73 for a Plex server and it should rarely run at 100% CPU usage, and never long enough to completely overwhelm the little CPU cooler. However, I'm concerned about potentially damaging the motherboard by drawing too much power through it, even if it's for only short periods of time. I have a 90 watt power adapter and my wall power meter says it never comes close to using all of that so I'm good on that front. In the Windows power settings I've set the "Maximum processor state" to 90% in hopes of limiting power draw there as well. If I remember correctly, in CPUID HWMonitor, under Powersackage it never goes above roughly 45W, but I don't know if that's an accurate metric for actual current draw.

My goal isn't to have an extremely fast Tiny system for my Plex server, but just to have something a bit stronger than a dual core CPU in it without spending a bunch of money, and I happened to have the i7 4770S available. If using the 4770S isn't viable or safe, I'll probably just go with a cheap dual core T series CPU. Any insight you have with this would be greatly appreciated.

Okay, so, before I say anything, keep in mind that I am a Rando on the internet and a single point of data. You do everything at your own risk. Anyway, the current throtteling seems to be universal. I can also face current throtteling on the i7 4750HQ though not as bad. I used Intel XTU to carefully undervolt the chip as much as I could to get more performance out of it. Since it's operating under a strict 45w budget, inching down it's voltages in some areas let me get some more performance out of that budget. Obviously the mobile i7 4750HQ can get much better performance per watt than the i5 4590. (It even out performs the i5 4590 when installed in a B85 Desktop board. :O) That said I only tested the fat i5 4590 for about an hour. I suggest you install Intel XTU and do your own testing and observations. But yeah, I don't THINK damage is a concern because the system itself will literally just go 'No, you get 45 watts. No more. I don't care if both CPU and GPU are running, you two can compete for watts.' I can't even find away to override it. That said, I briefly tested a 3770K in an M92P Tiny and that did not current throttle at all. It overheated and shut down in Cinebench. Do don't try it on an M92P Tiny.

I did upgrade from a 65w brick to a 90w brick though I found the use cases of exceeding 65w to be rare. I had to run a CPU and GPU intensive benchmark, spin the optical drive at full speed, and write 1gbps of data to the SSD, all concurrently, to get a bit over 75w. I don't think it's POSSIBLE to draw more power than that unless I somehow try to max out the USB bus power on every port. So 65w could have been a liability in some cases, I'm not worried with a 90w brick.

So I THINK you'd be fine using a 4770S, but it might under perform vs a desktop CPU and you should observe it with Intel XTU and a Kill-A-Watt to be sure. That said, these hacked up Chinese mobile CPUs seem MORE expensive now and I'd not suggest using one of those unless you were bored and had a lot of overtime money like I did. Nothing about the M93P Tiny really is a GOOD idea, it was just fun to do. I could have gotten some SkyLake thin client doing 4K HEVC no problem after all.