Celestia Forums

Hi, there,
After testing a lot of profiles to get Celestia take advantage of SLI, I have come to a kind of sweet spot to ensure that both GPUs are working.
Here is the code to add to your "nvapps.xml" file in /windows/system32/



Just copy/past the patch into nvapps.xml. Then, open the Nvidia control panel and browse to "New Application". Pick any item, change its value to whatever, change it back to the exact initial value and save. The CP is dumb. It will read from the nvapps.xml file but will save the settings to the registry only when you have saved changes. The CP does not read the registry! ... and to add to the confusion, the driver does read the settings from the registry, not from nvapps!

This shows that SLI is activated to display the highest possible quality:

Celestia is CPU-bound. SLI will kick in only for the highest quality rendering when asked to push as many pixels as possible.
Enjoy

Are you sure that you have a SLI because in your signature, you are 2 differents graphic cards

Fightspit wrote:Are you sure that you have a SLI because in your signature, you are 2 differents graphic cards

Yes, I have SLI for sure.
The FX5200 is disabled in the CP.
The SLI applet is configured for multi-gpu and sli load balancing.
I know about this stuff

Fightspit wrote:Are you sure that you have a SLI because in your signature, you are 2 differents graphic cards

The GeForce 7950 GX2 is a dual core (SLI on one card) video card.

I know it but for me SLI is a system with two graphic cards, that is all.

Fightspit wrote:I know it but for me SLI is a system with two graphic cards, that is all.

The 7950gx2 is made of two 7900xx graphics cards with integrated sli bridge and pci express switch. It is a stand-alone sli solution.
If you put two 7950gx2 in a system, you get quad sli.

Imagine a Quad SLI on Celestia ...

Fightspit wrote:Imagine a Quad SLI on Celestia ...

Well, it will probably not help much, unless you have got a an insane huge multi-screen setup with a Matrox one-to-four box driving, let say four 1600x1200 monitors.
Celestia is completely cpu-dependent and the cpu is the bottleneck.
I am planning a Conroe box. Just waiting for a good Intel motherboard with two 16x pci-e slots. Then throw another GX2 at it hooked to a Matrox box.
Not for Celestia, actually, but for flight sim and other apps I am working on.

Boux wrote:I am planning a Conroe box. Just waiting for a good Intel motherboard with two 16x pci-e slots.

The Conroe is officialy a Intel Core 2 Duo which is better than an AMD Athlon X2 or FX in all application software:
I know a french site which sell these processors and motherboard as well:

Actually, I am having a look at all reviews of new-generation Conroe-supporting motherboards that are being rolled out by the manufacturers.
Will pick up one by mid-october with an E6700 and 4 gigs memory.
Celestia is choking on 2gigs.
The magic box for multi-screen on one head is this one:
http://www.matrox.com/graphics/offhome/gxm.cfm
Three screens hooked together to render in SLI with the fourth screen kept separate as a working area for source code editing, compile windows and others.
Now I have yet to do initiate some serious negociations with the wife to clear the budget

Even If I have more money and I run 2X7600 GT in SLI and have 2 GB of RAM and a Athlon 64 X2 3800,I won??t be able to run a detailed model EVEN in 1024X768 and 8XAA.It??s a pity
Someone should say the truth:Celestia is very hungry with memory and speed,and you need about at least 500-1000 dollars to get a decent hires Celestia,just for a start.In my country,this is too much money and a Mastery??s scholarship is less than 300 dollars...
I have an Athlon 64 3000,1 GB RAM and 7600 GT and even Jupiter with 4k texture has slowdowns,when you take the speed to 1000X.I am using 800x600,2XAA e 4XAF.Someone should say the truth in Celestia FAQ:if you want Celestia very beautiful,You must have 2 GB of RAM and a 512 MB video card.I don??t know if it is the thousand galaxies,but I??m really disapponted how Celestia is demanding...

Boux wrote:Actually, I am having a look at all reviews of new-generation Conroe-supporting motherboards that are being rolled out by the manufacturers.
Will pick up one by mid-october with an E6700 and 4 gigs memory.
Celestia is choking on 2gigs.
The magic box for multi-screen on one head is this one:
http://www.matrox.com/graphics/offhome/gxm.cfm
Three screens hooked together to render in SLI with the fourth screen kept separate as a working area for source code editing, compile windows and others.
Now I have yet to do initiate some serious negociations with the wife to clear the budget

danielj wrote:This is not a simple discussion of
SLI.Your video card is a monster and your future
computer is a complete ABSURD.The only thing you
are doing is saying that YOU HAVE TONS OF MONEY
and want to humilliate everyone,saying that in
"normal" computers like mine,Celestia will run far
from it.

Even If I have more money and I run 2X7600 GT in SLI
and have 2 GB of RAM and a Athlon 64 X2 3800,I
won??t be able to run a detailed model EVEN in
1024X768 and 8XAA.

Since even with your monster computer,the frame rate
is a mere 27 fps.

So,this discussion is pointless...

Daniel,

I violently disagree (once more)!

You always tend to PROJECT respective discussions on
your PERSONAL setup and financial possibilities, which
sounds very selfish to me. While I could also afford
the same graphics setup as Boux has, I still use an
oldish FX 5900Ultra/256MB.

But nevertheless, it is valuable to read the respective
high-end reports by Boux, who is a) an expert in these
matters and b) can give us valuable practical hints
from his own experience.


Obviously, it is his hobby to have powerful computers.
That you should accept without envy. Of course also
Chris (Laurel) has a very fancy graphical setup. So has
ANDREA. Nothing bad about it.

Bye Fridger

I personnally like seeing what a nice PC can do. As I've said before, I'm building a new PC that some would see as extreme or expensive. AMD Athlon 64 X2 4400+; 2 GB OCZ Platinum RAM; EVGA NVidia 7900 GT 512 MB; 320 GB HDD; Abit AN8 32X motherboard; 600 watt Kingwin Mach1 PSU.

I've been saving quite a while for this PC, earning every penny for it. I actually have the damn thing built, but it's not working. From what I can tell, something is wrong with the Pheonix AWARD bios. I've had to return the mobo to Abit and patiently wait for them to send me a replacement. Spend $150 on the damn thing, I'd expect it to work, but I guess that's too much to ask. Oh well. I just hope that is the issue, and the replacement will work, and I finally will have a good PC, rather than my crappy current one ^^.

My point is, I'm upgrading to a set-up that will allow me to one day have an SLI set-up, and it's nice to know that Celestia will benifit from the effort I put into my PC.

danielj wrote:I have an Athlon 64 3000,1 GB RAM and 7600 GT and even Jupiter with 4k texture has slowdowns,when you take the speed to 1000X.I am using 800x600,2XAA e 4XAF.Someone should say the truth in Celestia FAQ:if you want Celestia very beautiful,You must have 2 GB of RAM and a 512 MB video card.I don??t know if it is the thousand galaxies,but I??m really disapponted how Celestia is demanding...

what do you mean by slowdowns?

I have a AMD 2600+ 1GB RAM and a GF5900 FX (128 MB) which runs very smooth on earth, mars and moon 8k textures.
no you don't need 2 GB of ram and certainly not 512 MB on your graphics card unless you want to load some really large textures like 64k VT-earth.

and I'm running on a dual-head setup with 2 LCDs both at 1280x1024.

so don't blame celestia if there is obviously something wrong with your pc-setup or configuration

phoenix wrote:so don't blame celestia if there is obviously something
wrong with your pc-setup or configuration

Yeah, danielj - try removing all addons and see if that speeds things up.
Then bring them back in one at a time and if you see one where it
suddenly grinds to a halt then that's what is slowing down your Celestia.

You have more than enough RAM etc and a decent video card, so you
should be able to run the default Celestia fairly rapidly. If it isn't running
quickly, then either you have one or more addons that are slowing it
down, or something is wrong with your computer, or something else is
competing with Celestia for processing power.

Personally, at one point I found that my Celestia was grinding to a halt
because of someone's nebulosity addons around Antares. As soon as I got
rid of that it sped right up again. So it's not always the addons that have a
zillion galaxies (though that doesn't help)...

Dear danielj,
please take a breath, read again t00fri's and Johaen posts.
You will find there both /very/ knowledgeable and wise approaches.
Believe me, I don't want to humiliate anybody and certainly not you in particular. This would be utterly ridiculous and pointless.
Years ago, I was pennyless too. It just happens that I have had some success in my profession and that I can now afford to put some /hard-earned/ money in this hobby.
Coming back to Celestia.
I think some users may be interested in having a preview of the potential of latest technologies applied to Celestia.
The engine will be more and more demanding on the hardware.
Big addons will require more and more memory and cpu power.
Very high detail/resolution rendering calls for high-performance graphics subsystem.
Widescreen and multi-display will become mainstream soon.
What is important is that basic Celestia still can run on any computer (this is important for me as I am involved in some educational activities in another part of my life - you know, third-hand computers and free time donated to some associations that take care of kids without a real family.
It is also very interesting to push Celestia to its knees on a high-end platform. There you see that the program is hitting a really bad memory management wall.
In the meantime, the reward is an absolutely gorgeous and smooth rendering experience, with all eye-candy switched on.
Accept the challenge, build up your life, take the lead and open your perspective

OK,but something is terrible wrong with my computer.I get out of Celestia most of my addons,but even so I get terrible slowdown with ISS-11A,reaching as low as 0.165 fps runing with the 32k Blue Marble Earth below,when the speed is set to 1000X.Even 4k Jupiter have a few slowdowns.Someone say that I should turn off the AA and AF,but people,I am using 800X600.It can??t have so much drop in perfomance as this.And I always use some AA and some AF.
My driver is Forceware 91.31.Should I update the drivers?If so,what??s the use for it,since almost no modification have been done from 91.31 to 91.47.Why we need to update to the newest driver always?
Again,my system is Athlon 64 3000,1 GB of RAM,VGA XFX 7600 GT PCI-E,HD Seagate 160.0 GB SATA 7200 rpm and Windows XP SP2.

Boux wrote:Dear danielj,
please take a breath, read again t00fri's and Johaen posts.
You will find there both /very/ knowledgeable and wise approaches.
Believe me, I don't want to humiliate anybody and certainly not you in particular. This would be utterly ridiculous and pointless.
Years ago, I was pennyless too. It just happens that I have had some success in my profession and that I can now afford to put some /hard-earned/ money in this hobby.
Coming back to Celestia.
I think some users may be interested in having a preview of the potential of latest technologies applied to Celestia.
The engine will be more and more demanding on the hardware.
Big addons will require more and more memory and cpu power.
Very high detail/resolution rendering calls for high-performance graphics subsystem.
Widescreen and multi-display will become mainstream soon.
What is important is that basic Celestia still can run on any computer (this is important for me as I am involved in some educational activities in another part of my life - you know, third-hand computers and free time donated to some associations that take care of kids without a real family.
It is also very interesting to push Celestia to its knees on a high-end platform. There you see that the program is hitting a really bad memory management wall.
In the meantime, the reward is an absolutely gorgeous and smooth rendering experience, with all eye-candy switched on.
Accept the challenge, build up your life, take the lead and open your perspective

I dunno, have you tried running a virus scanner or an anti-spyware tool recently?

runing with the 32k Blue Marble Earth below,when the speed is set to 1000X.

Daniel, I'm amazed you can get as high a frame rate as you do when this is going on.

By following the ISS at such a high speed, you are asking Celestia to load the entire VT but not giving it enough time to do so. The ISS is flying past tiles so fast that they're long gone before your disk can even think about responding.

Slow down. Take a deep breath. Enjoy the scenery.

danielj wrote:OK,but something is terrible wrong with my computer.I get out of Celestia most of my addons,but even so I get terrible slowdown with ISS-11A,reaching as low as 0.165 fps runing with the 32k Blue Marble Earth below,when the speed is set to 1000X.

is there a reason that you always test your performance with the time speed up by 1000? what about realtime?
i suspect your 32k texture is just too big to fit into your ram and your pc starts swapping. thats where things get really slow...

and lowering the resolution isn't the best way to get more performance. many modern cards are even "optimized" to a certain resolution.
my GF5900 FX runs very good on 1280x1024 but doesn't get much faster on 1024x768 or even 800x600.

higher resolutions just need more card-memory. ..