Fix Your Direct-X = Lockups Gone?

By Shirley Butler

I have been hearing from the flight simulator community that there has been lock-out and crashing problems with Riva TNT2 Ultra display cards, and other such cards. I have a Viper 770 32Mb TNT2 Ultra and it ran happily on my Pentium II 300 MHz computer, and I was very happy with it. However, that was until I upgraded my computer to a Pentium III 600 MHz running on a 133 MHz bus, then the lock-up problems began. My FS98 and FS2000 ran OK up to a point in up to 800x600, but above that the computer would lock up and my only way out was to press the reset button. Flight Unlimited III wouldn't get past the aircraft initialization.

Some well meaning men advised me that it was being caused by the power supply not being powerful enough to be able to deliver enough current to the computer, but the power supply that I have fitted in my computer is 350 watts, and that doesn't cure the problem. For a couple of weeks the problem was a challenge, after that it was an irritation, and after a month it turned into a pain in the butt. It nearly drove my husband Ted and myself up the wall and down the other side.

Anyway, for two months I tried to solve this display card problem. I tweaked the main system board's BIOS, and I made lots of adjustments to the display card's set-up until there wasn't anything left to tweak or adjust. The only way I could get it work with any reliability was to drop the bus speed to 100 MHz and run the CPU at 450 MHz - losing 150 MHz of processing power and lots of frames per second. Before you wonder or comment, yes I had 128Mb of 133 MHz memory on board, and yes the CPU was meant to be running at 133 MHz. This wasn't a satisfactory solution because if I had wanted a 450 MHz computer then I would have bought one, and the longer I used it in this configuration the more it irked me.

I began to suspect that it was an over heating problem so I played around with heat sensor settings in the BIOS, but none of that did any good either. With nothing left to tweak or adjust in the BIOS, Windows, or the display card settings, it began to look rather bleak as to whether I would ever get the situation sorted out.

As a last ditch attempt at sorting out the problem, I investigated the settings in DirectX, and that is where I solved the difficulties. The DirectX that I am using is DirectX7a, and all it took was a small adjustment to it to allow me to run my flight simulators in any resolution that I want, up to my monitor's maximum resolution of 2048x1536 without locking up. The performance of the Viper 770 isn't degraded either as I still get really great frame rates and smooth flying. For instance in FS98 I get about 150 frames per second.

If this fix works for me, then it is quite possible that it will work for you as well, and to do it, just follow the simple instructions below:

Double click My Computer icon on the desktop.
Double click on the C drive.
Double click Programs Files folder.
Double click on the Directx folder and double click on the Settings folder that is in there
Double click on the Dxdiag icon. This should run the DX diagnostics utility. Click the Display tab and switch off the AGP support by clicking the AGP button.
Then click the Exit button and return to the desktop. You should now be able to run FS98 or FS2000 in any of your desired resolutions without the computer locking up.

I can't promise that the above fix will sort out your display difficulties, but as I said it worked for me. It's an easy fix to do, and great if it works for you, but its also easy to reverse if it doesn't cure your display problems in flight simulator.

Shirley Butler
Email Shirley

Shirley offers more information on lockups Here

Visit Our Guide to Hardware and Lockups Here

Jeff Bott offers an additional idea for solving lockups Here