installation was ok so the xorgsetup but when i typed startx the monitor shown sync out of range. then i tried to edit manualy the xorg settings, xorgconfig, but then i got: "No screens detected"
tried with many different settings but still nothin'...
monitor is samsung syncmaster 753dfx, on msi geforce nx6200ax...
anyone help?
thanks!

If model numbers mean anything, then your monitor is newer than my Samsung SyncMaster 712N. If your monitor is newer then DDC probing should work.

In the very first section of xorg.conf, the section titled Modules, add the following:

# Allow DDC probing of monitor
Load "ddc"

This command will require X to try to communicate with the monitor and hopefully the monitor tells X the appropriate horizontal and vertical sync frequencies. Hopefully.

If that fails then grab a copy of Knoppix and if Knoppix boots into X, copy the resulting /etc/X11/xorg.conf to your Slack box.

how do i edit this? when i tried to open /etc/x11/xorg.conf itsaid Permition denied!
???

make sure you are logged in as root.

I have had good luck using xorgsetup and following the commands too. [edit] didn't realize you have used xorgsetup already... I would try xorgconfig again and dial down what you want your monitor to do and then run xorgsetup again.

although taking advice from me at this point is a bit of "the blind leading the blind"

Welcome to the often cantankerous and user-hostile world of Unix-based operating systems!

Unless purposely configured otherwise, most files on your GNU/Linux box not located in your home directory will require root privileges to obtain full access.

All files located in the /etc directory are considered system configuration files. Roughly speaking, this collection of files is the system equivalent of the Windows registry. Roughly speaking! If you used the older Windows 3.x operating system, then these files are similar to the old INI files.

You need to edit the /etc/X11/xorg.conf file using root privileges. From the command line type:

su root

The su command is the substitute user command.

When prompted type the password for root. If you are successful at getting past this exercise you then can edit this particular file.

If you are really new to GNU/Linux, consider making a backup of the file before editing:

cp -p /etc/X11/xorg.conf /etc/X11/xorg.conf.bak

When you are finished editing the file type exit to return to your normal user login.

I have a Samsung SyncMaster 793DF and I had a similar problem (I think). Allowing DDC probing like Woodsman said:

didn't fix the problem either. I ran xorgconfig originally with settings that I thought were correct for my monitor and then when it failed initially I ran it "scaled back" a bit in terms of the refresh rates and I still get the same thing. When I run startx it seems to start then the screen goes blank and there is a green box on the screen with "Hz?" floating around similar to the message I get when my monitor is unplugged from my computer.

I'll try the Knoppix suggestion though and let you know how that goes, but I'm baffled.

To edit at command prompt type su then give passwd then pico /etc/X11/xorg.conf.
Your monitor Hz and Vt refresh ranges should be in monitor manual,back of monitor or available from google or Samsung web page. To start you can use nv driver(#18).
Later you can deal with nvidia driver install. Have fun.

it's ok mate, i fixed it! finaly!
@SaintsOfTheDiamond:
when you start startx, and when the screen goes off, just press Ctrl+Alt+"+" on your numpad. keep pressing till you get a veeeeryyyyy huge screen working and thats it. after this (or before???) you can install the driver for your graphics and it will be ok!
thanx to all!

I'll give that a try when I get home and let ya know how it goes.

The documentation (that I was able to find anyway) for Samsung was pretty crappy. The manual that came with my monitor referred me to a site that didn't exist anymore and when I searched the Samsung site and Google the values I found still didn't seem to satisfy Xorg.

Got these results in secs. 1280x1024@65hz max resolution
30-70(Hz Freq)
50-160(Vert.Freq.)
Stick this to side or back of monitor for future use.

Those are the values I found and tried the first two times but it still didn't work. I'm gonna try the other suggestions here in a little bit so hopefully I'll have it resolved shortly.

The Ctrl+Alt+"+" did the trick ... thanks.

I went through the Xorgconfig setup again and now I'm coming to you live (for now anway ) from my very own Slack partition.

congratulations!
there you go...