Windows 7 and low-res modes

Hello!
I've just upgraded my cab from XP32 to 7X64 and i've seen i'm not able to choose resolutions below 640x480 anymore.
Soft15khz works great with modes 640x480 & 800x600 but i can't use the other modes.
I know that soft15khz i mainly for XP but i just wanted to know if it's a driver related problem or an OS problem
Should i return to XP64 to use the mame native modes??
Is the a software hack or a method to allow resolutions below 640x480 in Win7?,
Thanks

What kind of driver/card do you use?

Works fine for me with a HD 4550.

http://images.arianchen.de/soft15khz...en_cat1103.jpg

Thanks for your reply SailorSat
I have a HD4850 wich was working great in XP with soft15khz
I'm using latest catalyst now 11.12
when i reboot after installing 15khz modes, screen is locked just before i can see the desktop
I've succesfully installed soft15khz once,i was able to see all modes,then i've try to add some MAME modelines (perhaps too many.....)and then it was blocked again....Don't remember what i've done to get it work :'-(
Perhaps i have to delete all entry in the registry under HKLM\CurrentControlSet\Control\Video to start from zero.....
By the way i use DriverSweeper after every uninstall of drivers to clean registry
Any idea????

EDIT: Can you tell me wich catalyst version do you use? Perhaps can i try with a known working version to test

Thanks

Well, i've just tried with a fresh install of Win7 X64 and it's the same problem :
I've installed Win7 X64 and then the Catalyst 11.12, reboot and i was unable too choose a lower resolution than 640x480 with Quickres, very strange
I've run soft15khz and install 15khz modes just to be sure and reboot
The screen was blocked just before seeing the desktop again
So i think i will reinstall XP X64...................

Perhaps it has to do with EDID and pehaps i need an EDID dongle but i've asked on several forum about my problem and no one seems to have encountered such a problem

EDID is really the worst thing included in Vista/Seven for emulation....

The EDID dongle won't help you. At least not the "default" soft-15khz one.

As i don't have foun a solution, i've returned to XP X64 and all is working great
Perhaps later i'll try again.....
Thanks

EDIT : You don't have told me : Which version of catalyst are you using in your snapshot??????

Thanks :)

Actually I don't know ^^
I think it was 10.3 though.

I think i've a big problem with Win7
It's related to RDPDD or "Remote Desktop"
I don't know if it was my source of problem but i've uninstalled ALL the RDPDD driver or services ( those adapters that we see grayed in soft15khz in the top of the list), and i was able to select every resolution that soft15khz offers
I think those RDPDD drivers make a lot of confusions, sometime i was not able to set 800X600, why i don't know!
Quickres was unable to read resolution and can't change them....
And the Windows desktop properties let me choose 800X600.
But now it works great
I've not tried with Win7 X64

Do you ever have problems with those RDPDD driver, Sailorsat????

Another found:
Before i was not able to use Directx10 resolutions, only DirectX9 worked
Now without those annoying drivers, it works!!!

Hm... Thats actually a very interesting discovery. I'll do some tests asap.

Rochabian, how did you uninstalled ALL the RDPDD driver or services ?

I have the same problem in Win 7 + HD 4870 X2

It's my second HD 4870 X2 (yeah they will all go hell one day!) and I was not able to get it running in XP again ;-(.

Thats why I switched to Win 7. Now I can't use res below 800x600 (and even this res is lost after a reboot and must be changed back to 800x600 again.).

Soft 15 muss be started as ADMIN on Win 7 or it won't remeber your configuration!

I have the 4550 as well, and I finally managed to get the soft15khz to install (didn't realize I had to run as administrator! Thanks! :)), but I cannot get the refresh rate to show up as 15khz even though I can select 320x240. Any ideas on what to do? I am using Windows 7.