chaoscreater

Distinguished
Dec 26, 2008
76
0
18,630
Hi guys, this isn't really a overclocking but rather an underclocking question.

First of all, here're my specs:

Pentium 4 550 3.4Ghz
ASRock G41M-S3
Corsair Value Select DDR3 PC10600/1333MHz CL9 2GB


Now before I go on, please don't ASK me why I have a P4 or tell me to upgrade blah blah blah.......this is my old HTPC so i just wanna keep it the way it is, I have another gaming rig as my main PC already so this is just for work purposes. I've had multiple questions about this in my last topic and ppl just don't seem to read at all.

Ok so with that out of the way, I wanna underclock coz when I don't use it to play games, which I do occasionally, I use it mostly for work purposes and I want to run it at a lower temperature and use less wattage. After all, I don't game that much so don't wanna pay heaps for my electricity bill.

By default, my motherboard sets the settings as follows:

FSB:DRAM ---> 1:2
Timings: 6, 6, 6, 15, 64
VCore voltage (CPU Voltage): 1.375V
DRAM voltage: 1.53V
NB voltage (Northbridge Voltage): 1.251V
VTT voltage: 1.35V
CPU Frequency: 200Mhz
CPU Multiplier: 17

This setting usually runs at around 40~45C average, and uses around 23~24 watts. My motherboard comes with 2 nice programs called ASRock OC Tuner (for overclocking), and ASRock IES (Intelligent Energy Saver). I use ASRock IES most of the time when I'm working, i.e when I'm not using my PC for gaming. What ASRock IES does is it automatically lowers the CPU voltage, and it saves quite a lot of power for me this way. It also displays the CPU Power used in terms of watts, as well as how much KJ (Kilojoule) my CPU consumes per second.

WITHOUT turning IES on, my CPU uses around 55~60W, and of course the default VCore is 1.375V as I mentioned above. If it is turned ON, my CPU uses around 23~24W and it lowers the VCore to 1.264V. The VCore changes slightly, as IES automatically changes it so sometimes it'll be at 1.2560V, sometimes 1.2640V but those are within the small ranges so that's fine.

Now, going from the default 60W CPU Power usage to 23W is pretty good to me, that's like triple the amount of wattage decreased. But what I found out is that IES doesn't actually set the VCore at a lower voltage, what it does is that it lowers the "actual" voltage to a lower value but doesn't actually change it. Of course, the voltage IS lowered, in CPUID Hardware Monitor PRO, CPU-Z, Everest & CPU-Cool, they all showed the VCore as around 1.264V in real time so that's correct. But what i'm trying to say is, since IES is a software that automatically does all this, it's not the same as doing it from BIOS where the setting is an actually permanent change.

It's just like saying when you overclock using SetFSB, or RivaTuner or any of the graphics card or CPU overclocking softwares, they only overclock the settings when you RUN the software, i.e you have to boot into your Windows to do it. But it doesn't change it straight away after your PC is turned on, therefore the actual settings remain the same and are only changed by the software when they're run.

Ok so my point is, because IES only lowers what the current actual VCore is, which is by default at 1.375V, that means I can use ASRock OC Tuner to lower the VCore, and that IES will automatically adjust it to an acceptable value.

So FINALLY here's the problem, I wanna underclock it since IES only lowers the VCore at the default setting, so if I underclock it then I can run it at an even less workload. So I lowered the VCore from the actual 1.375V to 1.30V, I lowered the DRAM to 1.48V (lowest value OC Tuner allows me), and lowered the VTT to 1.3V, and lowered my CPU FSB from 200Mhz to 180Mhz.

The temperature is lower now, from the previous 40~45C to 35~39C. BUT, the CPU Power uses 43~44W now, WTF??


It makes no sense when I lowered the FSB, lowered the VCore & DRAM voltages, and yet it uses more wattage than before??



For more info on my CPU, check these 2 links:
http://ark.intel.com/Product.aspx?id=27469
http://en.wikipedia.org/wiki/List_of_Intel_Pentium_4_microprocessors (use CTRL+F and type 550, that's the model of my Pentium 4 CPU)



Lastly, I know there's you can buy wattage meters like Kill-A-Watt to measure how much wattage you're using on almost any device, I'm planning to get something similar to measure the wattage output of my HTPC, but is there a software that can do this as well?? I can't seem to find anything on this on Google.
 

chaoscreater

Distinguished
Dec 26, 2008
76
0
18,630
coz I've said already, I wanna make it run at a lower clock to use less wattage, and thus less electricity or power. Again, this is just my HTPC so i'm only using it for work.



Also, I just wanna update something that I found after tinkering around with the settings. If i keep all the voltages the same, but only lower the FSB from the default 200Mhz to 160Mhz, i.e dropping from 3.4Ghz to 2720Ghz, then the temperature stays around the same if not slightly lower, the the wattage is slightly lower if not the same.

Well, this makes sense since this is what an underclocking is suppose to do as it puts less strain on the CPU and the rest of the components etc.

Another weird thing I found is that if I change any other voltage, such as VDimm, NB voltage, GTLRef voltage & VTT voltage, they don't affect the CPU wattage consumption. I can lower them without increasing the wattage, which is what should happen anyway. HOWEVER it seems that if I lower the VCore voltage, that's the one that increases the wattage for some reason.

So maybe there really is something wrong with the program, maybe it just sucks I dunno but it reported this quite accurately, but once I start to lower the voltages, logically it should show a drop in the wattage even more, or at least keep it the same but instead it just increases it......



Lastly, I think I have an idea of this weird problem. Every CPU has a range for their minimum and maximum voltages. According to Intel's info, my Pentium 4 550 3.4Ghz has a range of 1.25~1.4V.

Since I never really overclock/underclock the voltages, I don't have much experience or knowledge about this but what actually happens if you go over/under the range?? I know the range is the acceptable values but what effects will you have if you don't stay in the range?


As I stated in my first post, ASRock IES automatically lowers the current VCore, but just like every other software for overclocking, they don't change it permanently like you do in the BIOS. Therefore, you can still adjust the actual VCore, and as I've said I used ASRock OC Tuner to adjust it from 1.375V to 1.35V.

However I just noticed that at 1.375V, ASRock IES lowers it to around 1.264V, which is already near the minimum range of 1.25V. By lowering the actual Vcore from 1.375V to 1.35V, and with IES automatically adjusting the value, it now shows it's using around 1.15V, which is now below the range specified by Intel.


I hope this isn't too confusing but maybe this explains something?
 

No. There is no way for software running on a PC to measure the power consumption of that PC. The PC does not have the sensors.

Even your 60 watt to 23 watt reading is just an estimate, and in my opinion, not a particularly good one. :)

A Kill-a-Watt meter, or something similar, is the only accurate way that you will be able to determine power consumption.

My suggestion is to restore the BIOS settings. Then drop the CPU multiplier to 12 or so. Then start reducing CPU voltage until your system is no longer stable. Reducing CPU voltage will have the greatest effect on power consumption. Next, make sure that SpeedStep is enabled so your system spends as much time as possible idling.