quick guide to underclocking cpu with rmclock?

hey people,

i'm trying to undervolt a core 2 duo cpu to decrease heat and fan noise. can anyone give me a link to a short guide, or write one up on the fly? i am using vista....when i decrease the voltage, nothing seems to happen, so i must be doing something wrong.

 

I've just started my day's work, so I can't write a long essay now (although I have described the process in at least one post during the past few months).

Make sure that you have selected the right states (for both mains and battery) in each of the pre-defined profiles and then at the main profile page (see RMclock1.jpg), select which profiles to use for mains and battery (RMclock2.jpg). I use performance on demand for everything. The result is RMclock3.jpg.

I'm using XP, but the latest RMclock beta. I would expect it to run the same under Vista. If you still can't get it running, look in the R Mclock forum.

Hope this helps,

John

 

I remember some previous post was made before and rmclock doesn't work in vista for some reasons...

 

man....why am i not getting these threads in my searches?

for some reason, when i go to the specific profiles, i can only choose one index instead of choosing all of them. is that a problem?

edit: i seem to have gotten the voltage to drop choosing index 6 and dropping that to 1.137. do i check stability by running a cpu stress test? i can only seem to get cpu-burn in b/c it seems that tat and prime 95 are incompatible with vista.

 

1. This is the recent thread about RMclock (but not specifically Vista).

2. Maybe the missing link is the need to clock on an index entry. You can then change the voltage. See the attached.

John

 

for some reason, when i have it on performance on demand, it will only go to .95 v and the clock speed will not go over 1 ghz, even when on a stress test.

 

Assuming that you have the necessary states all selected on the Performance on Demand page, then I wonder whether there is a interaction with the operating system. You could try the integration with the OS on the management page and the OS settings on the profiles pages. I have kept these separate so that OS power management and RMclock work independently.

John

 

i think it will just put it on the max setting on the 12x. it still runs much cooler. i have gotten down to .987v and my load temps went from 71C to 61C. thanks a lot for your help, john!

 

So what are you using for 12x?

My T5600 is at 1V and my T7200 is at 1.05V.

John

 

i have a t7200 and using .987v.

unfortunately, i am using cpu burn in as a stress test, and it only tests one of the cores, so stability may still be an issue if both cores are utilized. i have been running 20 minute stress tests and have had no errors.

 

Are you able to create two instances of CPU burn, perhaps with different names in different places and then run them concurrently. 0.987V is low but not impossible.

John

 

hrmmm...i think it is too low....after i finished the cpu burn test, i have been having some problems. i have high cpu usage for no reason, and i can't seem to properly access rmclock.

edit: i restarted my computer and everything was okay...got rmclock to open, it it somehow changed so that the voltage was 1.237 for all indeces. i don't know if the problem was the low voltage or if it is rmclock + vista is the issue.

 

Evidently, the settings were not saved, but that is no bad thing until you know that everything is stable. Interesting that your T7200 defaults to 1.237V. Mine has 1.187V default at 12x (the T5600 has 1.25V default at top speed).

I would suggest that you subscribe to the RMclock forum. Getting the software to work properly with Vista is ongoing and your experience could help. I'm still waiting for my Vista upgrade.

John

PS: Maybe some clues here.

 

actually, this is not my computer, but a review unit. i'm trying to find fixes to reduce fan noise.

 

Regarding fan noise, maybe my essay here will be of interest.

John

 

i love that you write essays.

my fan noise is really due to the fact that i'm using an ultraportable with fairly high end components. the fan is always on.

 

That's the strength of my Q35: They didn't overdo the high end components, but it would be better still if I could find an L7200 or L7400 CPU.

John

 

My T7200 undervolts to .987V at 12x multiplier. It's .950V at the lowest multiplier. The goal is to supply a steadily increasing level of voltage for higher PStates, otherwise your CPU might choke from lack of power.

Below is a screenshot.

 

problem is that i can't do power on demand in vista. when i switch to that profile, it cuts my throttle and clock speed to 1 ghz and i can't get out of the 6x multiplier even when i run a stress test.

 

I see that RMclock 2.25 has been released, but full Vista compatibility is still work in progress. However, I still wonder whether the current problem may relate to how RMclock co-exists with the Vista power profiles. I have a similar conflict with the Samsung Battery Manager and the solution seems to be to let RMclock manage the voltages without trying to over-ride the OS power profiles.

The other question, more directly relating to your fan noise problem, is what does perfmon show for the %C3 state on both mains and battery?

John

 

hrmmm...i have 2.2.

so it seems that performance on demand is functioning now. another problem in addition to the fan noise is the cpu whine. i tried the cpu whine fix where i run the hlt command....but then i started losing battery life at a fairly rapid pace...almost 1 hour less than i was usually getting. it fixed the whine, but i don't think the fix is worth 1 hour of battery.

one thing to mention is that the cpu whine only occurs when i am on battery.

another observation that i've made is that at times the fid doesn't match the vid. for some reason, i often have my 6x = 1.05, even though it is set for .95v. is that normal?

another thing that is surprising is that i have no improvement in battery life. i was expecting at least a few minutes more....

perfmon = xr perfmon?

 

Some observations:

1. Undervolting may not increase battery life unless the CPU is running at above minimum speed.

2. Not sure why 6x is showing as 1.05V. That is wrong. Check how the profiles are defined.

2. Read this RMclock forum thread about the CPU whine.

3. Perfmon is the XP performance monitor which can be run as Start > Run. Does Vista have the equivalent? C3 state is deeper sleeper and RMclock has an option to use C4 (even deeper sleep) when C3 is enabled. It all helps towards power saving. On battery and light usage, XP shows C3 state at least 75% of the time. Maybe Vista is worse in this area.

I also had some comments about battery life and power consumption towards the end of my Q35 review (link in signature). For example, I found that using a bluetooth mouse was bad news for battery life.

John

 

ahhh....i never heard of perfmon before (shows how much of a software noob i am....).

vista hides the run function, fyi. anyway, perfmon does exist. how do i chart the c3 state?

edit: i don't think you can plot c3 time on vista. for you (the powerplay bios thread), it seemed that c3 was under processors. i do not have an option for it under processors. but if i just tell from cpu whine, the processor is always (95% of the time) on c3 in battery mode. since there is no cpu noise while on ac, it would imply to me that it doesn't enter c3 or 4....though when on very high load, there is a very loud whine periodically.

 

I can remember perfmon at the moment because something recently reminded me that it existed. (One reason for my essays is to capture in print my thoughts before they evaporate - I can always search the forum to find out what I was thinking).

To add %C3 to perfmon in XP, just right click on the window and select Add Counters, then choose from the list. I can't see why this would be changed in Vista, but the process is not intuitive.

So you didn't manage to nail down the CPU while yet. I don't know whether to thank Samsung, XP or RMclock, but neither of my Samsung notebooks makes any nasty CPU noises at the moment. Or maybe my old hearing has lost the high frequency coverage. I thought one of the possible fixes what switching direct from C2 to C4. In RMclock, Advanced, Platform, there's enter C4 on C3 command.

I'm now using RMclock 2.25, but I don't know if it will help your Vista problems.

John

 

i finally found the %c3 after digging through all the menus and clicking on random things. on battery, it is on c3 80ish% of the time while almost never on ac.

anyway, the quick fix (hlt command) works, but at the cost of a surprising amount of battery ife.

i have had the enter c4 on c3 command the entire time. but it doesn't seem to be entering c4. =/

 

some additional tidbits....rmclock doesn't seem to be recording some things correctly. when i first ran cpu burn in, only one core clocked and throttled up. also, cpu load was 100%, but os load flucuated a few percent from zero. when i ran it today, both cores have their clock and throttle all the way up. for core 0, both cpu and os load was 100%, instead of just having cpu load at 100%. on the other hand, core 1 has 0% for both os and cpu load. finally, my vista sidebar widget that displays is at 100% all the time, even on idle.

 

Thanks for the update.

I think the enter C4 on C4 fix means the OS thinks it is C3 but may be in C4. 80% C3 on battery and under light load is in the right range. I think that whether a computer enters C3 while on mains power depends on the BIOS. My Q35 does go into C3 on mains but the X60plus does not.

I believe that running the HLT command when idle confuses the reporting of OS load since the CPU will always be busy, running HLT if nothing else. Fortunately, my computers doesn't seem to be afflicted by the CPU whine problem. Looking at the posts on this problem, HP seems to be the worst affected.

John