Aggressive undervolting (X41 Tablet - Pentium M 758 LV)

[Binh]

I am a new guy here, I had OC my X32(735 to 780), this is my setting:
14 1.480V
Of cource, I didn't use 17X step

May be it is wrong in the voltage for 14x multiplier ? 1.48v for 1.86Ghz (?) is too much for a Dothan chip. My 745 dothan is stable at 14x @ 1.116v (overclocked to 133Mhz FSB).

[Investinwaffles]

Small update, I applied Arctic Silver 5 to the CPU (and what i think is the north or southbridge?)

Basically, i disassembled per the instructions posted earlier in the thread, and removed the heatsink/fan assembly.
Then i hit it with some 800grit sandpaper after cleaning the old thermal compound off. After applying the new thermal compound and re-installing i saw a 1*C drop in idle temps, and a 3*c drop in load temps. My machine now loads at an astonishing 58*C after 2 hours of Prime95!

It didnt make a huge difference, but it is definately noticable. It takes longer for the machine to heat up, and quicker to cool down (due to the increased efficiency of the heat transfer between the CPU and the heatsink).

While i was in there, I used compressed air to clean out all the dust, and some q-tips + isopropyl alcohol to thoroughly clean out the fan and other areas.

[astroidea]

YEZZ I've been looking for a program like this to undervolt
I've managed to run mine at .700V for the 6x multiplier and .896V for the 15x multiplier on my X41 tablet. Stability was tested with 25 kill deathmatch of UT2004 .
This is one extra notch above the lowest i could go without crashing.
I wish it had a setting lower than .7V for 6x.. since it looks like it could even go lower!

Is there any program that could be used to OC the X41 btw?

[Investinwaffles]

I dont believe so. The FSB is locked, and pinmodding is not possible with these soldered processors.

I also wish I could get it to go lower than .700v because it has been absolutely rock solid so far.

[cristimm]

I run with this settings:

M -- it worked -- safe (+1 step)
06 -- 0.700 -- 0.700
08 -- 0.700 -- 0.716
09 -- 0.732 -- 0.748
10 -- 0.764 -- 0.780
11 -- 0.796 -- 0.812
12 -- 0.828 -- 0.844
13 -- 0.860 -- 0.876
14 -- 0.892 -- 0.908
15 -- 0.940 -- 0.956
16 -- 0.972 -- 0.988

I tested them quick, 5 minutes each in prime95 and then added a step for safety.

[p78]

Thanks for the NHC tip !

I noticed that my fan wouldn't turn off though, even if the CPU temperature would be 40C on my X40 ... I then applied the "NHC Fan Control fix" here : http://forum.thinkpads.com/viewtopic.php?p=466541 and now my fan is turning off when CPU is at 50C

[Investinwaffles]

Thats great, I have my fan running on low pretty much all of the time (it kicks up to the 2nd fan speed at 55*C).
It does keep the computer overall cooler. Most of the heat buildup is from the southbridge heatsink (near the ram cover).

I did some "smoke tests" to see where the air comes from (blew through the fan with a lungful of smoke :p ). The main intakes are near the ram, and southbridge vents so it stands to reason that airflow over those components will keep it from getting too toasty.

[systema]

I'm planning on AC5ing my x41t, how long did the disassembly, applying, and reassembly take? Thanks

[Investinwaffles]

Probably 2 hours from start to finish, pretty straightforward mod. I used the lenovo repair manual to tear it down.

[systema]

Tore mine down to system board yesterday..to see if i could fix my loose hinge (to no avail) I tightened the bottom-side two screws on the hinge, which tightened the rotating, but there is still some play when it's locked in place. Not sure what I can do...will probably have to live with it...

Thanks. I plan on opening it up once again when I install the SSD.

[systema]

Quick question: does NHC work fully with win7?

[bemymonkey]

Quick question: does NHC work fully with win7?

Dunno, but RMClock does a great job.

0.700V @ 6X
0.892V @ 15X

1.5GHz version...

Idle temps are down to ~40°C, and full load is around 63°C - both with the fan completely off.

[PhreakShow]

It might work, but you can also use the newer rmclock which does quite the same.

[Investinwaffles]

NHC has been out of development for quite some time, so I would recommend RM clock as well. Im using it on my X301 and its working very well

[eyestrain]

On the newest hardware, I might favor RMclock or CPUGenie.

But on older hardware, NHC might be fine. With a Pentium M, I don't know if there's any advantages to RMclock, as it might not have had the P-M portion of the software changed in a long time for all we know.

Could try one, and if you like it and it works well, you don't really need to try another. I tried both a few years ago, and preferred NHC. Something may push me to change, but til then, NHC works well for my computers, even CD T60p.

Actually I really want to use PHC, but that's another board section--Linux.

[cristimm]

bad post

[Donald]

I broke the cpu fan connector with my fingernail and weakened it thus the wires came out of the connector.

Does anybody know how the wires are supposed to mount into the harness? I remember red being towards the edge - but yellow and black? Dang it.

X41 T 1866


----edit----

Found it:

Red Black Yellow



I was of course (thanks to the motivation and repair manual link from THIS THREAD) trying to get a few decibels more of silence as my fan seems to run a lot and my cpu freq doesn't throttle down as much in W7 as it did in XP (1200 MHz W7 v 800 MHz XP throttle down).

And I did find some old dried out grease on the cpu. Not a bad idea to freshen it up folks.

Anyway what a crap cpu fan connector - very weak, I just touched it and it disintegrated. Well, I threw some superglue on it and all is well after reassembly. And a little super glue on the left hand side ALT key pivot connector. Dang it!

Donald

[ReCreate]

Dunno, but RMClock does a great job.

0.700V @ 6X
0.892V @ 15X

1.5GHz version...

Idle temps are down to ~40°C, and full load is around 63°C - both with the fan completely off.

How did you get it so low? It crashes here if the voltage goes any lower than ~.920
I have the same exact CPU as the one in the title, Windows 7 and have been using NCH.
Those voltages are even lower than the ones in ULV processors.

[astroidea]

How did you get it so low? It crashes here if the voltage goes any lower than ~.920
I have the same exact CPU as the one in the title, Windows 7 and have been using NCH.
Those voltages are even lower than the ones in ULV processors.

Lucky guy.
I have 4 x41t, two of them undervolts well, one hardly undervolts at all and one undervolts moderately

[ReCreate]

Perhaps some of the power saving configurations are getting in the way, all of them should under-volt equally.

These are the stable voltages i've gotten so far on here, in order of which i tried.

Code: Select all

6x .7V
8x .876V -> .844V -> .796V -> .764V
10x .892V -> .812V -> .780V
12x .924V -> .908V -> .860V
15x .956V -> .940V

[astroidea]

All 4 of my tablets are using clones of windows installations.

They shouldn't undervolt equally just as CPUs of the same model don't overclock equally. There are variations between CPUs based on manufacturing date/process/location/etc. When the CPUs get manufactured, the manufacturing process is constantly being changed/improved. You will find that newer CPUs of the same model will on average undervolt better than older CPUs of the same model.

Also CPU manufacturing is such a fine and delicate process that no two CPUs come out identical. There is a manufacturing tolerance going on here and there will be some coming out on the short end of the stick.

[Bibin]

Hee hee, that is agressive?

At 6x both my X41 tablet and T43p take only .7V and remain stable. Are my CPUs special or something?