will downclocking GPU bring down the temperature?

Dear all,
I use my 7807 to program most of the time and the GPU temp is around 50c, but the noise of the fan is kind of annoying. If I downclock the GPU(say half the original freq), will that bring down the temperature and silent the fan?
thanks so much

 

I believe underclocking will reduce the temperature, but of course the performance will suffer also.

Check out these threads for information on cooling:

http://forum.notebookreview.com/showthread.php?t=304671
http://forum.notebookreview.com/showthread.php?t=60914

Search is your friend

 

Downclocking the GPU will not affect temps. Only undervolting it will, but this requires either modding of the BIOS or a hardmod of the GPU itself.

 

Like the CPU, the GPU has a voltage det for it.......the voltage will not scale with the clock speed, it will stay constant, and dictate the temperature of the GPU. (I'm just trying to give you a little explanation to go along with sgogeta4's answer)

As long as your temps fall within the safe operating range, under 105D, and the notebook doesnt freeze, then dont worry about it. If its continuously freezing, or overheating, contact Gateway about servicing or replacement. If its out of warranty, check out the disassembly guide and replace the thermal compound on the GPU and clean out the notebook interior.

 

That's not entirely accurate, while reducing voltage will have more effect, decreasing the clock speed of any chip does lower it's power usage. The GPU should be dynamically lowering its voltage and clock speed though, so there's not a whole lot "lower" to go generally.

To elaborate, most of the heat generated by any processor is created by the loss of electricity as heat during transistor switching. The faster you switch the transistors the more often you're creating excess heat.

 

Nice, I will go ahead and try to follow the guide to undervolt my p7805u... I'll post my results if I have success.

 

Thats not exactly accurate either. Unless you flash the BIOS, the GPU is going to draw the default voltage.....much like any other hardware, save the CPU (which has various thermal controls). Using a kit of memory as an example, it has an SPD chip integrated that tells the motherboard what settings and voltages to default to (Most kits will fall back to the JDEC settings, so that optimally a kit will always boot and allow the user to configure it as needed).

With the GPU in this instance, we know that the 9800M GTS is actually a flashed 8800M....whats different? The clock speeds....to achieve those clock speeds they probably had to boost the voltage a bit to ensure stability across a large number of units.

So, by simply underclocking the GPU, you might see a bit of a temperature drop, but it would be minimal, and probably disappear under load. Why? Because the GPU is not going to scale the voltage like a CPU would. Now, if you can find an app that lets you adjust the voltage, you'll see some positive changes in temp readings.

In my opinion, in the end....you can replace the thermal compound, clean out the chassis, but other than that I dont see a viable solution thats going to make a world of difference.

 

You could always put the laptop in an ice cold bucket of water; that'd cool it down some

 

I decided against undervolting my GPU since I am actually overclocking my 9800 GTS to 750 core/ 950 mem/ 1750 shaders, and I am using more voltage than default. I would be able to play games on that level of OC for about half an hour until the temperature reached over 70 degrees after which it crashes. Lowering the voltage would cause instability, so I just went ahead and undervolted my CPU from 1.375 to 1.150 and now my CPU runs cooler (30 degrees stable and 40 max) and my GPU runs a bit cooler too as a consequence, giving me more play time before I reach the 70+ temps. Looking to get a cooling pad for my lappy, ordering one this week.

 

The 9800M GTS isn't an 8800M per se, the 8800M's are all clipped G92 (8800 series desktop) core vs the 9800M GTS which is a slightly underclocked G94 (9600GT). The 9800M GTS does use more power than most of the 8800Ms due to it's high clock speeds and having the same amount of shaders etc "enabled".

The OP was asking about underclocking at idle, assuming you can go lower than the idle clocks already are you'll definitely see some, however marginal it may be, improvement. At full speed certainly a lower voltage would be the only thing that would make a difference. I've seen some reports that the BIOS can be modded to lower the voltages using NiBitor but I personally haven't tried. You should be able to adjust 2d and 3d clocks and voltages, but it's kind of an iffy procedure if you screw up and go too low you can have serious problems. If it has a clock control/voltage control IC like some of the desktop cards you might be able to "softmod" it to try out different settings and worst case it would lock up.

 

Heres a good write-up/definition of the 9800M GTS.
http://www.notebookcheck.net/NVIDIA-GeForce-9800M-GTS.9918.0.html
Maybe this discussion is the base for a good tutorial/guide on lowering the GPU temps?