Underclocking my 8800 GTS 512

ScretHate

[H]ard|Gawd
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How far can I safely underclock my 8800 GTS 512? The reason I'm interested is that it runs awfully hot (75C) when I'm not gaming and just browsing the web for instance. I'd like to reduce its heat and power consumption while not engaged in gaming.

It currently has a core clock of 650MHz and a memory clock of 972MHz.
 
Damn, it should be underclocking itself to 2D clocks when you're not gaming or doing any other 3D rendering. You check the fan to make sure it's working? Even if the clocks are sticking on 3D clocks, it still has to have a load in order to make it heat up like that. Even when my GTX 285s stick on 3D clocks (sometimes happens when I pause folding@home on them), they cool down to ~50°C.

What are you using to monitor the clocks and temp? I would download Rivatuner to check what the fan speed is running at and if it's too low, turn it up. But you shouldn't even have to do that. I would pull your card out, blow it out and make sure everything looks/works good. Then investigate as to why your card isn't downlclocking itself to 2D clocks in the first place.

To answer your question though, if your card is stuck at 3D clocks, then you can manually downclock it in Rivatuner to the lowest setting it allows and it'll still be more than enough for your desktop/2D environment.
 
take it apart, clean it and reapply some paste. that did wonders for my old g80.
 
The fan works just fine. The fan automatically adjusts itself to idle at 75C. If I turn the fan up to 60% (up from 37%) I can get it down to 50C. With the fan at 100% it goes down the low 40s.

I've never had an Nvidia card that underclocked itself. I've owned a 6800GT, 8800 GTS and now this one. All of them have run at 100% all the time.

What would be a safe range to underclock to? With EVGA precision, the lowest I can go for the core is 485MHz.
 
Since I believe the 6800 series the cards have had a 2d profile and a 3d profile. When in 3d the card runs at a higher clock speed then when on the desktop. In 2d the clocks are slow. I believed reference 6800 series cards fan ran 100% all the time but when the 7800 series and above came out there were fan profiles into the bios. My facts may be a little skud because I used to work for one specific nvidia AIB at that time so what they did may not be what everyone else did.

What I suggest you do is what was suggested above, Clean the fan of any dust, remove the heatsink and re-apply themral paste. If the temps from doing that alone are not good enough, I'd suggest you make a custom bios and make a fan profile to your liking using nvflash to backup and flash the new bios and nibitor to modify and customize a bios for your card.

Software solutions are okay but can get annoying at times.

Nibitor
http://www.mvktech.net/component/op...temid,26/func,select/id,135/orderby,2/page,6/

NvFlash
http://www.mvktech.net/component/op...temid,26/func,select/id,127/orderby,2/page,3/
 
Does Afterburner or Precision work on those older cards? That would at least tell you if the card is downclocking correctly. What driver version are you using?
 
Does Afterburner or Precision work on those older cards? That would at least tell you if the card is downclocking correctly. What driver version are you using?
I'm using the newest drivers, 258.96.

I'm also using precision. It doesn't downclock at all.
 
g92 didn't underclock at idle, the gtx 200 series did - hence the power saving hybrid SLI coming and going in a flash. However, 75oC is still too hot for that card at idle, so either, as others have said, it is getting loaded by something even at desktop, or your cooling is compromised, prolly by dust. Get some compressed air inside that thing. In terms of underclocking, you can take that thing as low as it will go, try rivatuner too (this can sometimes go lower than afterburner) just bear in mind that this can cause instability so just treat this like inverse overclocking. Also note that memory underclocks are said to be the more troublesome, although I have no experience of this myself.
 
If you really want to do this, you need rivatuner, and then you can setup a TEMPERATURE profile.
I used to do this and have my GTS downclock to 200 or 300mhz core (i forgot how low rivatuner lets it go...) and something like 500-600 for the ram (again, whatever the lowest setting was...). It would automatically downclock to this when i quit gaming on the machine.

Setting the profiles is a pain in the ass, cause you need to know what temp(range) your card is idling at, what temp is the threshold for 3D (You CANT make a profile based on GPU usage, which sucks...)
and what temp you think the settings should downclock, based on the temp(or range) the GPU is when you stop gaming/3D.

Now, I dont do that anymore, cus its kinda redundant and counterintuitive, since running the fan at a set percentage locks it to that, regardless if the temperature continues to climb. (i.e. Furmark, OCCT, GTA4..., ect) Evidently 75% fan, isnt enough to hold the temp below 72C, when running something extensive like the apps/games above.

The stock setting will never go above 80% fan, from what i have seen anyway. But then again it will idle at 37% everytime.

BTW: I am overclocked (sig) and idling right now@ 37% fan. The current temp is 56C. You may want to check the airflow of your computer case, or get a new case all together, cause you should NOT be idling that high. I have to murder my GPU (OCCT,furmark) to get it that high, even then I dont see 75-80C ever, with stock fan settings too.
 
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My case has decent air flow. I've got two medium yate-loon 80mm fans in front and another two in the back. The card isn't dusty, as it's fairy new (it's an RMA replacement).

Right now I'm running it at 485MHz with the fan at 50% and it's idling at 52C. I guess I'll grab riva tuner and see how low I can go.
 
If you do get the best results in rivatuner, you can simply save these as a profile in afterburner. Then set this as your 2d profile and default clocks as 3d profile.
 
Underclocking shouldn't cause any drama at all. Undervolting, however, is where you would need to test stability. Power savings comes from undervolting, and undervolting is likely to require underclocking to work.

Don't expect less power/heat if you lower the clocks without lowering the voltages.
 
Don't expect less power/heat if you lower the clocks without lowering the voltages.

Not true. When I downclocked, the temps would idle 2-4C lower than normal. Sometimes it would be so low that my 3D profile would not activate, after launching a game, because the temps were so far below the threshold I set.
 
How far can I safely underclock my 8800 GTS 512? The reason I'm interested is that it runs awfully hot (75C) when I'm not gaming and just browsing the web for instance. I'd like to reduce its heat and power consumption while not engaged in gaming.

It currently has a core clock of 650MHz and a memory clock of 972MHz.


are you running dual or single display? since i noticed no one asked that..
 
Not true. When I downclocked, the temps would idle 2-4C lower than normal. Sometimes it would be so low that my 3D profile would not activate, after launching a game, because the temps were so far below the threshold I set.

2-4C? Please. I think the OP is looking for a lot more than that and you won't get it without also lowering the voltage.

You're doing the opposite of overclocking. In the CPU world, your heat really picks up when you have to crank the voltage.
 
2-4C? Please. I think the OP is looking for a lot more than that and you won't get it without also lowering the voltage.

You're doing the opposite of overclocking. In the CPU world, your heat really picks up when you have to crank the voltage.

Yes, to put this in very clear terms:

dynamic power = capacitive load * frequency * voltage^2

static power (leakage) is also directly related to voltage (do not remember the equation off-hand).

Frequency only affects dynamic power. Voltage affects both dynamic and static power, and you get a bonus because of the voltage^2 relationship with dynamic power.

Since you need a certain voltage level to support a given frequency, you should definitely reduce the voltage when downclocking to save power. Reducing the frequency only gives you a little taste of what is possible if you reduce the voltage AND frequency.
 
2-4C? Please. I think the OP is looking for a lot more than that and you won't get it without also lowering the voltage.

Sooooooooooooo.....
It's still true. Whats your point?

Either way, its pretty damn obvious OP has a serious issue, since his card is idling 20C higher than normal.
 
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