Windows 7: Problem with unsigned driver I can't fix

Hello,
I'm running Windows 7 x64 since October without any problems. Yesterday I had to change the CPU cooler (and I cleared the CMOS) I found out that my TV tuner (twinhan DVB-T) drivers weren't installed anymore. I don't know if those two actions are linked somehow cause I had a system update from windows update in the same day before my discovery that could have changed some kernel configuration, wanted by MS of course.
The problem with those drivers was that they're not signed so I had to enable Test Mode with a tool dseo13b.exe and everything was working just fine.
Now this! I've run out of options I don't know what to do anymore.
I tried to enable test mode from tools, command line, disable the signature control from registry and services. NOTHING they won't load. I also tried to sign the driver with this guide but it continues to be read as not digitally signed even thought it clearly is from a verification from Microsoft WDK.
So every time I boot the system I get an error that says the .sys driver could not be loaded because it's not signed and I have to either cancel the sys from system32 folder thus it won't load at all or press f8 and disable the signature enforcement control which makes the driver work, but it only applies for the current session. At the next restart I'm back to the start.
I found a "script" called ReadyDrive Plus that automatically selects that option in f8 on boot but I DON'T KNOW WHY since I have Linux installed too with GRUB after I select in this order :
1- from GRUB windows 7
2- from Windows loader ReadyDriver Plus

It goes back to GRUB loader! So useless!

Apparently my only solution is to select f8, do you know any other method to select it automatically? Or why the hell Test Mode doesn't work anymore ?

Edit: I misread your post, I was posting to suggest using DSEO... Sorry about that.