Don't Laugh - Serious Question

[sweetca]

I am getting too hot at night in my office (computer room). I have decided to revert my Core 2500k, which was running at 4700 mhz @ 1.38v, back to stock frequency; I honestly just don't need the extra juice at this time.

I was wondering, perhaps at the default 3300mhz, I could even lower the voltage below stock and help cool the room down a bit? Has anyone tried such a blasphemous thing? Anyone out there get some crazy low voltages they wish to share?

System:
Corsair Obsidian 650D
Corsair Professional Series Gold 850-Watt
Gigabyte GA-Z68X-UD3H-B3 Rev 1.0
Core i5-2500K - 3.3GHz - LGA1155 - Sandy Bridge
Corsair Hydro Series H80 Liquid CPU Cooler
ASUS - GTX770 -1110MHz core
Kingston HyperX 8 GB(2x4) - 1600 DDR3
Vertex 3 SSD -120G

 

[aigomorla]

it will probably reduce your temps by like .2C overall, unless u leave your room closed, and it has no way to exchange air outside.

In seriousness, unless your room is a closet, lowering voltage that much, you probably wont feel it, and having a fan in your room would negate it without any difficulties.

 

[sweetca]

First, thanks for your response.
Second, is that 0.2C or 2C?

 

[aigomorla]

First, thanks for your response.
Second, is that 0.2C or 2C?

0.2C lol.... Im not being exact, im guessing 0.2 would even be the extreme higher end.. as it will probably do less then that...

Its like will a 50W light bulb heat your room up?

 

[sweetca]

I guess I should add for clarification. The room isn't too large, approximately 120sq ft, and I keep it at 23.3C (~74 Fahrenheit). I assumed that the CPU running at 40-60C, depending on overclock/voltage, would add a fair amount of heat to the room.

 

[aigomorla]

I guess I should add for clarification. The room isn't too large, approximately 120sq ft, and I keep it at 23.3C (~74 Fahrenheit). I assumed that the CPU running at 40-60C, depending on overclock/voltage, would add a fair amount of heat to the room.

11ft x 11ft room... as i said, unless u had 0 windows in that room, you wouldnt feel it.

you would literally need a 9sqrft closet for you to feel "something" and thats with the door closed.

 

[sweetca]

"Its like will a 50W light bulb heat your room up?"

In truth, I am not sure. When the system is overclocked, there is quite a bit of heat being generated out of the vents from the case. I keep the door closed (because I must - Kids sleeping), and I assumed that the heat would make somewhat of a difference. Certainly, I could be mistaken.

 

[sweetca]

11ft x 11ft room... as i said, unless u had 0 windows in that room, you wouldnt feel it.

you would literally need a 9sqrft closet for you to feel "something" and thats with the door closed.

Ok, thank you for your informative responses. Perhaps it is my fat ass that is just generating too much heat :\

 

[cbrsurfr]

Do you run distributed computing or something where the CPU runs at or near 100%? If not then lowering the voltage won't make much of a difference.

 

[tolis626]

Ok, thank you for your informative responses. Perhaps it is my fat ass that is just generating too much heat :\

Definitely the fat ass, I suffer from the same problem.

Speaking a little more seriously, underclocking/undervolting the CPU really won't do much. It's like aigomorla said, a 50W light bulb wouldn't change your room temps much. In more extreme setups, like OCed CF/SLI, the GPUs can make temperatures rise in the room the PC is in, but there we're talking about >250W of heat per card and more than 500W in total for the GPUs alone, so one would be well in the 600W range of total system power consumption. In such a case yes, undervolting would help. But in your case, even while overclocked your system doesn't produce that much heat. Buy a kill-a-watt to see exactly how much heat it dumps in your room.

With all that said, you can have hot spots in your room if airflow isn't good. In my case, when I keep my computer room closed, the area where the PC and my 40" TV are is quite hotter than the rest of the room, mainly because the TV radiates quite a lot of heat. Opening a window or using a fan to disperse the heat will even out the temperatures and they will usually stay where the room temperature was before, or like 0.1C higher at worst (Especially in a 120sq.ft. room, mine is about 70sq.ft.).

 

[frozentundra123456]

I think it definitely could heat up the room, but most of the heat will come from the gpu, assuming you are using it heavily. The TDP of the 770 is over 200 watts (230 I think) and that combined with an overclocked cpu with both at full load, along with the other components, could consume 300 plus watts, which will definitely be enough to warm a closed small room. For comparison, space heaters usually have a low setting of 750 watts and a high setting of 1500.

The problem is that setting the cpu back to stock might save only a small portion of that max load consumption, and if the system is not being used heavily it doesnt matter anyway.

 

[KingFatty]

You can fully test the wattage consumed when overclocked vs underclocked (btw that's a thing where people save money/heat, referred to as underclocking).

Also, you may be able to find wattage charts for your CPU running full-load at different voltages/clocks.

Someone looked into a similar aspect. But what are you doing with the chip? Is it sitting at idle during this time? Or are you letting it crunch away at 100% usage?

Perhaps you may simply have some malware that is using your chip without your knowledge. When idling, the CPU should produce very little heat, regardless of whether you are overclocked or underclocked or stock. Maybe elaborate on your other settings?

http://hardforum.com/showthread.php?t=1620183

Here's an example showing that idle power consumption decreases by like 3 watts when you underclock, compared to stock settings:

http://forums.anandtech.com/showthread.php?t=2311086

 

[sm625]

I do it all the time. I have a pair of shortcuts on my desktop that change the power profile from 100% to 50%. This reduces my clockspeed from 4.5GHz down to 2.2GHz. Most of the time I cant tell that it is running at the reduced clock speed. But when it does feel sluggish I just click the shortcut and it goes to full speed.

 

[BSim500]

I was wondering, perhaps at the default 3300mhz, I could even lower the voltage below stock and help cool the room down a bit? Has anyone tried such a blasphemous thing? Anyone out there get some crazy low voltages they wish to share?

A lot of people undervolt for various reasons (HTPC's (Home Theatre) & Silent PC Enthusiasts do so for minimum possible fan speeds under load, those into green computing do so for energy savings, etc). At stock 3.4GHz, I can get my i5-3570 voltage down to 0.888v load (and 0.640v idle) stable. Even with a mild OC to 4GHz, it's still no more than 0.996v load. Best CPU I ever had (and the number one reason I'm in no rush for Haswell).

As for the effect on room temperature, according to the CPU OC calculator, your CPU at 4.7Ghz @ 1.38v is pushing around 148w. Stock i5-2500K is nearer 95w. Stock undervolted, you may get that down to 70-80w or so, so overall, you're looking at 70-80w savings. Under constant 100% load throughout the day that's around 1kw of energy (and heat equivalent) per 12.5hrs. That may well have a noticeable mild impact on room temps (1-2c or so depending on room size, ventilation, etc) throughout the day but mainly only if you heavily constantly load your CPU (eg, batch video encoding session). If you have the headroom, then undervolting is still worth doing anyway simply for lower fan speeds & CPU temps under load (you can easily knock off 5-10c CPU temps with an undervolt). I have mine running 600-700rpm (cheap 212 EVO) and temps never go above 50c gaming / 55c Prime. You literally have to put your ear to the case to tell if it's on (LED's aside).

 

[NTMBK]

Make sure all the power saving features like Speedstep are enabled on your CPU- I know people often disable them when they're OC'ing. Letting your CPU clock down when idle will save a good amount of power.

To be honest though, it's your GPU that will pump out the most heat.

 

[SlowSpyder]

I have a power hungry 9 series AMD FX in an 8'x9' room. I know your pain OP. There is a difference between running this thing balls to the wall vs. stock frequency with power saving features on and undervolted. But generally it seems to be my graphics card that really pumps out the heat.

 

[sweetca]

Ok, thanks everyone!

These are some genuinely excellent comments, and suggestions for me to consider. I will certainly scope out those links as well.

I definitely find myself leaning more towards computer efficiency these days, in contrast to all out Power & Speed; this results in a cooler, quieter, and less expensive environment.

And truth be told, I hardly ever need ~5k CPU speeds. I just don't play games the way I used to, and I don't do any Distributed computing or Encoding type activities. I will check out those links and play around with underclocking some.

It does also appear that I could benefit from underclocking the GPU (If that is a thing), or perhaps buying something more appropriate to my needs.

Thanks again to the AT community. I've been in AT-land for ages (longer than even my avatar represents), but I am not a heavy poster. It is nice to see that the members of today exhibit the same thoughtfulness and helpful attitudes, as many of us did back in the Celeron 300 o/c to 450 days

 

[Maximilian]

Solution:

 

[teejee]

0.2C lol.... Im not being exact, im guessing 0.2 would even be the extreme higher end.. as it will probably do less then that...

Its like will a 50W light bulb heat your room up?

50W continously is more than 1 kWh per day, that will definately heat up a small room noticably. A wall radiator in a small room is around 600W peak power, but average power is much less.

 

[Zstream]

Ok, thanks everyone!

These are some genuinely excellent comments, and suggestions for me to consider. I will certainly scope out those links as well.

I definitely find myself leaning more towards computer efficiency these days, in contrast to all out Power & Speed; this results in a cooler, quieter, and less expensive environment.

And truth be told, I hardly ever need ~5k CPU speeds. I just don't play games the way I used to, and I don't do any Distributed computing or Encoding type activities. I will check out those links and play around with underclocking some.

It does also appear that I could benefit from underclocking the GPU (If that is a thing), or perhaps buying something more appropriate to my needs.

Thanks again to the AT community. I've been in AT-land for ages (longer than even my avatar represents), but I am not a heavy poster. It is nice to see that the members of today exhibit the same thoughtfulness and helpful attitudes, as many of us did back in the Celeron 300 o/c to 450 days

Same thing here but I use sleep mode much more often as it's still summer.

 

[Idontcare]

I am getting too hot at night in my office (computer room). I have decided to revert my Core 2500k, which was running at 4700 mhz @ 1.38v, back to stock frequency; I honestly just don't need the extra juice at this time.

I was wondering, perhaps at the default 3300mhz, I could even lower the voltage below stock and help cool the room down a bit? Has anyone tried such a blasphemous thing? Anyone out there get some crazy low voltages they wish to share?

I ran tests like this with my 2600K, for the long version of the story you can check out my thread Effect of Temperature on Power-Consumption with the i7-2600K

For a shorter version, here are a few relevant points:

All that heat coming from your computer is heating up your room, and as the ambient temperature of the air in your room rises, so too does the electric leakage in your CPU which then results in the CPU burning even more watts of power than before.

At 2.0GHz clocks, with the Vcc reduced to 0.822V (IBT stable), the 2600K consumes 24W at 38°C under load with IBT.

At 3.4GHz stock clocks, with the Vcc reduced to 1.038V (IBT stable), my 2600K consumes 65W at 48°C under load with IBT.

Pushing it up to 5.0GHz, with the Vcc set to 1.488V (IBT stable), this 2600K consumes 227W at 93°C under load with IBT.

Depending on the magnitude of the under-clock, you are looking at the possibility of considerably reducing the heat output.

 

[sweetca]

IDontCare, those are very interesting graphs. Thanks! I think this will be a fun project. How low can I go. Heh.

And Max, yes, I have seen this type of device before I generally dislike fans, especially the stand up kind. Hard to explain, they just annoy me.

 

[BonzaiDuck]

Not familiar with the Gigabyte motherboards or BIOS's, but . . . I don't get it. Really.

You can keep the over-clock, set the EIST, C1E etc. to Enabled. Most of the time, I'd think your processor won't be pushing more than 1.1V. The processor won't heat up. You won't have excess power consumption.

If you can make the system sleep, that's even better. Even with mild gaming, my temperatures don't exceed 50C, which is off the chart in IDC's graph.

Maybe I'm missing something . . . somebody speak up if that's the case.

 

[frozentundra123456]

OP, as I said, I think the majority of the heat given off will come from the gpu, especially in gaming. Depending on the game, the gpu will probably be running at close to 100% utilization, while the cpu might be not running at full utilization.

If you dont game much, you could sell the GTX770 and use the money to purchase a new Maxwell GTX 750Ti. That card will use approximately 1/3 or less power than the 770, and still provide a decent gaming experience, although of course not nearly as powerful as the 770.

 

[Geforce man]

I'm genuinely curious what the power consumption of my 2700k @ 1.28v @ 4600Mhz would be. It seems like a decent balance between the 3.4Ghz 65w and the 227w @ 5.0Ghz, at what I would consider a ludicrous voltage.

Either way, IDC as per usual with the awesome information!