Soft15khz problem SOLVED

[Minwah]

Here's an odd problem. I have built a PC using old stuff I have, and had to use a mobo with PCIE...I have not used a PCIE card before.

So I've installed the Soft15khz 15khz modes...and as a rule it works well. What's odd is that firstly, the 31khz modes are still there - ie 640x480 and 800x600 display at 31khz...not 15khz interlaced. 720x480 however is displayed at 15khz interlaced.

The second odd (really annoying) thing is this...I have my desktop mode set to 720x480. If I boot with a PC monitor plugged in, the 720x480 15khz mode is used and therefore I have to unplug the PC monitor and plug in my Scart TV - this is fine. BUT if I have the Scart TV plugged in when I boot, the windows resolution reverts to 1024x768, so I have to switch over to the PC monitor.

The first issue I can live with because I don't really need 640x480 15khz interlaced (although it would be useful). However the second is a problem as even though I can boot into frontend at 15khz, if I need to quit into Windows it goes to 1024x768 and I need to switch screens.

I either need to fix the root cause of the problem (not sure how to go about that), or prevent Windows from changing resolution to 1024x768. Is that possible?

[Minwah]

I haven't really solved this but I have kindof made some progress. I'm using a GeForce 6600 PCIE, and was using ForceWare v197.45.

So I tried using ForceWare 93.71, which I have previously used with success with an AGP GeForce card. With this version of the driver, I do not have the problem with the interlaced modes...great...but there is a different problem. Some of the low res modes do not work correctly, I am not sure why, but some work (eg 320x240) and some don't (eg 240x240). This is a bigger problem than my original problem really.

I don't have a solution but having now tried several ForceWare versions, I can say the following:

a) v175.15 and lower - not all low res modes work with this card.
b) v185.85 and higher - the interlaced modes do not work with this card *

* 720x480 interlaced works in v197.45 - I did not test in all other versions but it does not work in some versions.

I guess somewhere between these versions something significant changed. I may try and work out exactly which version, in case by chance there is a version which works correctly.

I don't really need the interlaced modes for games, but they would be useful for admin. If I go back to v197.45 I can at least use 720x480 interlaced when I really need to (although I can't boot into it, I can boot into a low res mode).

[SailorSat]

Hm... Maybe your LCD reports 640x480 31kHz and this overrides the custom modes in newer drivers.
To be honest, I haven't tinkered around with S15K for quite some time.

[Minwah]

Hm... Maybe your LCD reports 640x480 31kHz and this overrides the custom modes in newer drivers.
To be honest, I haven't tinkered around with S15K for quite some time.

Could be. I've now gone back to v197.45 and the only interlaced modes which don't work are 640x480 and 800x600+ so it's pretty good really.

Still odd that I have to boot into a low res non interlaced mode or it defaults to 640x480 31khz.

Thank you for your work on this by the way. Soft15khz saves a lot of hassle!

[Minwah]

So I was booting into 640x288 for a while...and at some point this stopped working (Windows kept reverting to 640x480).

Now I have tried with an EDID dongle and I can get 640x480 15khz interlaced, and (so far) everything works fine.

Problem solved!