Hi AVSIM members.

 

Nu-be to this site. If posting in the wrong area please advise and I shall do my best to adjust.

 

I have always wanted to build a flight simulator. Tried and failed. This will be my third attempt.

Have all the parts required for a PC to run FSX, this will include a projection of the screen via

a 5000 lumen unit onto a flexible curved screen. Have started the motion platform and have

motors and control board ready to go 3 DOF motion.

 

Anyway onto the problem I have, I dare say this topic has been discussed before so if anyone

can suggest links then please do so.

 

I Have two graphics cards ASUS NVidia GTX 790 linked via motherboard and connection link

ribbon. NVidia drivers up to date and running NVidia inspector with a few tweaks. Card No1 in

the PCI-E slot marked x16 on the MB as the main driver and the second card in the second

PCI-E slot marked x2 on the MB as GPU support for the first card.

 

Running NVidia inspector shows GPU card No1 at around 80% usage when flying over EGHH

airport frame rate around 45-59 FPS. CPU is an intel I7 3.6 GHz overclocked to 3.9 GHz on air

cooling at a temp of 94d.

The second GPU card No2 via inspector shows it running at 0% usage.

 

I know from reading forum posts that FSX runs better from faster CPUs and GPU not used so

much.

 

Question being am I using both graphics cards to display FSX in PhysX mode connected to a Matrox

tripplehead2go via DVI cable to HDMI. or am I only running off one card. Also because one of the

cards is in a PCIE slot marked x2 am I throttling card No1 to the lower slot speed.

 

Even though the performance is good I wander if it could be improved.

 

Thank you in advance IanMC

 

 

CPU is an intel I7 3.6 GHz overclocked to 3.9 GHz on air cooling at a temp of 94d.

 

I'll leave others to comment on the display questions but if your CPU is running at 94 degrees C, that's very hot! Apart from not being good for the longevity of the chip, it's getting very close to thermal throttling which will definitely affect performance in FSX. Such a small overclock should not produce that sort of temperature. What temperature are you getting running the CPU at stock speed? My current system (update soon, hopefully) has an i7-920 overclocked from 2.66GHz to 4.0GHz and peaks at about 65 degrees C with a Corsair Hydro AIO cooler.

 

I would check that the fan(s) on your cooler are dust-free and are running normally. If so, and you have a good quality air cooler, I would try re-mounting it with some new thermal paste. It may be time for a new cooler.

Thanks Vortex681 for the reply

 

Have checked heat sink and cleaned. Lapped and re-paste to CPU. Added a second fan blowing through the side of the heat sink.  

 

Running temps now on full load tops at around 59c

Normal running with low demand showing 42c

Running FSX on an approach to EGHI and EGHH shows a temp of 56c

The FSX display levels at high level with UK photo VFR installed version 3.

 

The CPU now running at 3.9 GHz. My MB does not support overclocking and via NVidia Inspector 3.9 is the best I can do.

 

Do you have any more advise

 

Regards IanMc

Have checked heat sink and cleaned. Lapped and re-paste to CPU. Added a second fan blowing through the side of the heat sink.  

 

Running temps now on full load tops at around 59c

Normal running with low demand showing 42c

Running FSX on an approach to EGHI and EGHH shows a temp of 56c

 

That's more like it! Hopefully someone will step in and help you with the graphics problem now, although you may have more success in the "Monitors | Multi-Monitors | Video Cards | Drivers" forum.

 

Out of interest, which motherboard do you have?

vortex681

Main MB details

 

As-rock H77 Pro4-M

Invy bridge Rev 09

Socket 1155 LGA i7 3.4 HGHz

 

Have noticed when using CPU-Z the core speed and core voltage is not constant.

 

Cheers IanMc

Sounds like your second card isn't functioning in SLI. I'm no expert at SLI, so someone who is will have to help. 

 

 

 

Have noticed when using CPU-Z the core speed and core voltage is not constant.

 

 

 

You mean the frequency and voltage drop at idle, and increase under load? If so, this is normal behaviour to save energy.

 

 

 

Hi Guys

 

Just found out the MB I have does not support SLI only crossfire.

 

Looks like a new MB required.

 

Any advise on a good MB for my

2 x GTX 760 Geforce cards

1 x i7 3.4 ivy bridge CPU 1155 LGA socket

24 gig DDR3 2 x 4 gig 2 x 8 gig

Looking to run FSX only as main programe

Have  20 x usb devices attached.

Tripplehead2go 3 x24" monitors plus DVI projector 5000 lum 1024x768 Main screen

 

Thanks IanMc

I tried running FSX with two ATI cards (in ATI's version if SLI) many years ago and saw no benefit.

 

I did Google "FSX and SLI" and came up with several good posts.

 

Here is one of them. where Word Not Allowed chimmed in.

 

Best wishes!

You'd be better off selling the two 760's and replacing them with a single 960 or 970 for FSX.