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Dynamic over/underclocking a 7900GT???

Posted: Tue Mar 28, 2006 3:19 am
by Big Pimp Daddy
Hi, recently got a 7900GT (quite a step up from a 5200fx), the stock cooler made my ears bleed, so have put a VM-102 on it. Temps are better than the stock cooler by a few degrees, but I want to able to run the case fan at lower speeds, without anything catching fire. Also I would like to overclock slightly when playing games. Basically I want to have four different states (including the stock settings); idle - heavy underclock, 2D load - slight underclock, and 3D load - slight overclock. And I would like for the software to do this automatically, though manually switching wouldn't be much of a hardship. Also I would love some kind of dynamic voltage adjuster, but i'm guessing that's more difficult.
I've tried using coolbits, but it seems to only have two states, and i'm not sure if it's actually changing anything as the values are always the stock ones whenever I go back to it.

Basically I would like to know what software would be able to do some or all of the things outlined in my meandering prelude. Any help appreciated, Thanks in advance.

Posted: Tue Mar 28, 2006 3:24 am
by jmke
Rivatuner is what you want:)
http://www.guru3d.com/rivatuner/

you can adjust clockspeed of 3 different stages (2D, low 3D, full 3D) change fan speeds (if you use the onboard fan connector) and assign profiles and shortcuts.

Posted: Tue Mar 28, 2006 8:24 am
by ROcHE
Rivatuner still does not support the 7900GT :(

Posted: Tue Mar 28, 2006 8:38 am
by jmke
ow; sorry , didn't know, thought it was all one big happy family

Posted: Tue Mar 28, 2006 2:11 pm
by Big Pimp Daddy
Bravo sir! You raised my hopes and dashed them quite expertly.

A little Futurama humour there... Anyway, thanks, I assume rivatuner will support the 7900GT eventually, given that it's only two weeks old i'll let them off. Any ideas for a stop-gap solution? There must be someone out there with an underclocking fetish and a 7900GT. Surely?

Posted: Wed Mar 29, 2006 2:56 am
by DG
Could you pls post some pics with your 7900gt and VM102? I'm planning the same configuration, and wonder how it looks like...:)

Posted: Wed Mar 29, 2006 2:56 am
by DG
double post, pls delete

Posted: Thu Mar 30, 2006 11:19 am
by jmke

Posted: Fri Mar 31, 2006 2:27 am
by Big Pimp Daddy
Thanks, I will give Powerstrip a try.

As requested, here is a picture of the VM-102 installed. I apologise in advance for the crappy picture-phone quality. You can't really see in the photo, but the left (in the picture) side of the top heatsink actually protrudes just past the end of the graphics card. Shouldn't be a problem in most cases, just something to be aware of.

Posted: Fri Mar 31, 2006 2:30 am
by jmke
for a picture-phone that pic is amazingly high quality.

Posted: Fri Mar 31, 2006 6:16 am
by b1_
How about moving the camera back a bit Big Pimp Daddy so we can see your whole setup. Looks like a Scythe Ninja CPU heatsink, but from what I can see in that pic it looks like the Ninja and your VM-102 get very close. Any problems with airflow? How quiet?

I was thinking I wouldn't be able to buy a 7900GT because it would be too hard to silence, but if you have had no problems perhaps I was wrong and I can have power + silence afterall.

Posted: Fri Mar 31, 2006 10:11 am
by Tzupy
I don't understand how the Ninja and VM-102 fit together on Asus A8N-SLI mobo, and there's even a bit of space left!
How are the temps on the 7900GT depending on the case airflow (back fan rpm)? BTW if no software solution is available, get a 3.5" fan controller!
You could try opening a couple of PCI slots below the 7900GT, to improve airflow over the lower part of the VM-102 (which IMO is a piece of junk, by comparison with the fins / heatpipes upper part).

Posted: Fri Mar 31, 2006 8:03 pm
by b1_
Tzupy wrote:(which IMO is a piece of junk, by comparison with the fins / heatpipes upper part).
The lower piece is only meant to collect the heat not dissipate it. The design of it assumes the PCI slots are closed, as they should be to improve airflow. The sexy copper part above the card is the dissipator, and it's in the airflow corridor.

Posted: Sat Apr 01, 2006 5:20 am
by Big Pimp Daddy
As requested, another photo, from further back. The ninja and vm-102 are pretty close, but not so that there's any danger of them interfering with each other. The vm-102 is a lot thinnner than the vm-101, which I don't think would fit unless you put the card in the lower pci-e slot. I don't think the proximity is harming airflow, I figure the closer they are, the more airflow is forced through heatsinks instead of just exiting the case ineffectually. The pci slot cover just below the card is already open, as i'm sure i heard somewhere that someone got better temps with it open.
I am still in the process of testing tinkering modding and tweaking (atm it's idling at stock speeds at 50 deg with a 140mm yate loon at about 1000rpm), should have it all done this weekend, then I'll post it in the gallery with all the details anyone could ever want.

Posted: Sat Apr 01, 2006 7:13 am
by b1_
Thx Pimp Daddy.
Big Pimp Daddy wrote: I'll post it in the gallery with all the details anyone could ever want.
Yes, please do. I don't know about anyone else but I'd be very interested in all temp readings etc.

Btw, the VM-102 is supposed to be able to handle up to 70W of heat (source). A 7900GT draws 64W (source). If it's the case that the 64W drawn by the 7900GT is converted to 64W of heat then the VM-102 can handle the 7900GT.

Posted: Sun Apr 02, 2006 9:27 am
by Ackelind
Everything drawn by computers is converted to heat.

Posted: Mon Apr 03, 2006 11:40 am
by Ozy666
Ackelind wrote:Everything drawn by computers is converted to heat.
That's generally true for all power...eventually...

Everyone should be ashamed of themselves that running their computers 24/7 is contributing the eventual heat death of the universe. :)

Posted: Wed Apr 05, 2006 9:29 am
by Tzupy
Aerocool claimed 70W for the VM-101 too. And I'm sure it can do that, with 2,000 rpm 120 mm back fan. :lol:
With a 1,000 rpm 120 mm fan however, a GFX card that does about 50W is reliably cooled.
The original poster has a 1,000 rpm 140 mm fan, which pushes about 30% more air than a 120 mm fan, and it's noisier too.
I infer that with a 120 mm fan at 1,000 rpm (or lower rpm for his 140 mm fan) the result would be higher temps than with the stock cooler.
I wonder what would happen if he would put a Nexus on the Ninja?

Posted: Wed Apr 05, 2006 11:07 am
by nutball
I'm just putting together a configuration of a VM-101 -> 92mm Nexus -> Ninja -> rear exhaust hole, all in a single duct. This is in an attempt to cool a 7900GT + A64 X2 3800. Dunno if it'll work, but that's half the fun, innit?!

Posted: Thu Apr 06, 2006 4:15 am
by Tzupy
@nutball: if it works it would be sweet indeed!
But why a 92 mm fan as exhaust, and not a 120 mm one?
And what about the cooling of the mobo voltage regulators / chipset (where applicable)?

Posted: Thu Apr 06, 2006 5:05 am
by Live
Tzupy wrote:Aerocool claimed 70W for the VM-101 too. And I'm sure it can do that, with 2,000 rpm 120 mm back fan. :lol:
With a 1,000 rpm 120 mm fan however, a GFX card that does about 50W is reliably cooled.
Well according to xbitlabs the 7900gt outputs about 50watts, a bit lower even:
Image

http://www.xbitlabs.com/articles/video/ ... gtx_6.html

Posted: Thu Apr 06, 2006 5:58 am
by nutball
Tzupy wrote:@nutball: if it works it would be sweet indeed!
But why a 92 mm fan as exhaust, and not a 120 mm one?
And what about the cooling of the mobo voltage regulators / chipset (where applicable)?
The fan is to be sandwiched between the VM-101 and the Ninja -- the 92mm being just smaller than the head of the Ninja makes it easier to enclose in a duct.

If it isn't quite enough I'll try either a second 92mm in a push-pull through the Ninja, or a 120mm maybe.

As for the VRMs and chipset, they'll just have to fend for themselves (the chipset is passively cooled anyway). I'm hoping that with CPU+GPU heat all ducted directly out the back of the case that the PSU + front intake fans will keep the interior cool enough.

Posted: Thu Apr 06, 2006 7:52 am
by Tzupy
@Live: after seeing the Xbitlabs review I stick to my previous opinion, that the 7900GT draws (maximum) about 5W more than my current 6600GT.
Why? Because Xbitlabs' power draw tests are not exhaustive, and I believe that Oblivion is stressing a 7900GT more than 3DMark.
So the 7900GT should be coolable by a VM-102 (which BTW has only 29 fins, not 32 like the VM-101; I counted them this morning :lol:).

@nutball: I suppose that the gfx card is in the lower slot, otherwise how can you sandwich a 25 mm fan between a VM-101 and a Ninja?
So the Ninja won't get fresh air, but some 45W of heat. Please report back on your temps. Anyway, I wish you best of luck!

Posted: Fri Apr 07, 2006 3:21 am
by Tzupy
@ B P D: To increase the airflow through the VM-102 & Ninja, you could apply some sponge / foam on the case side panel. That foam should block the air paths (well, as much as possible) that are not 'covered' by fins, thus forcing the airflow through the fins. If have you already done this, my apologies. I believe that your back fan at 1,000 rpm is a bit noisy, what about controlling it with Q-Fan? What would be the 7900GT's temps when the fan is at ~700 rpm?

Posted: Thu Apr 13, 2006 3:50 am
by nutball
Well I've half-finished my duct, shrouding the Ninja and directing the airflow out the back of the case. The 92mm Nexus is running at the low-end of a Fan-Mate, so ~700rpm I think.

I've got the VM-101 mounted on the 7900GT with a shroud to force air to be drawn through the fins only. Now comes the fiddly bit of joining the two shrouds together to form a complete duct (so the shroud in the VM-101 isn't actually doing anything useful yet).

I tried some quick load tests just to see what the temps are. The graphics card idles at ~50C, the CPU at ~25C. With two instances of RTHDRIBL running plus one of Prime95 for good measure the GPU is up at 84C, the CPU at 47C. I did some CPU-only tests yesterday whilst stability testing my undervolt (1.1V), with two instances of Prime95 the CPU was hovering around 45C (which is what my XP3200 Barton idles at :D)

The major noise sources are the seeks from my hard drive (why did I allow myself to seduced by a Raptor?) and the exhaust of the NeoHE 430 as it ramps up.

Posted: Mon May 22, 2006 6:22 am
by jmke
BUMP

http://www.guru3d.com/files/rivatuner/

• Added NVIDIA G71, G72 and G73 graphics processors support. Thanks to Andrew Worobiew for testing RivaTuner with NVIDIA GeForce 7300, 7600 and 7900 series.