1. does it need power supply?
I didnt saw any molex ports or anything like that.
So I just plug it in, downloaded and installed drivers and there is no sound.
I have 5.1 speakers and nothing is hearing.
Any help?

(I bought this used from local computer store)

You don't need an external power supply. But it sounds like you didn't connect the cables that came with the card. Do you have the installation manual and all the components that come with the card? Sounds like your missing something or didn't complete the setup.

Only thing im missing is somekind of adaptor for joystick/MIDI port.
But I found that '' i need more resources'' and computer give me this Code 12 error.
No idea what to do.

If it is an error code in device manager for the sound card this what microsoft gives for an answer to the problem.
Code 12
This device cannot find enough free resources that it can use. If you want to use this device, you will need to disable one of the other devices on this system. (Code 12)
Cause

This error can occur if two devices that are installed on your computer have been assigned the same I/O ports, the same interrupt, or the same Direct Memory Access channel (either by the BIOS, the operating system, or both). This error message can also appear if the BIOS did not allocate enough resources to the device.

Recommended resolution

You can use the Troubleshooting Wizard in Device Manager to determine where the conflict is, and then disable the conflicting device.

Disable the conflicting device
On the device Properties dialog box, click the General tab.
Click Troubleshoot to start the Troubleshooting Wizard. The wizard asks you some simple questions and provides a solution to your problem based on the answers that you provide.
Follow the resolution steps provided by the wizard to resolve the problem

Sounds like you need to disable the other sound device on the motherboard or if you have another sound card installed to remove it.

I disabled everything expect Terratec and it still shows error

Have you tried doing a microsoft update on your system and do a system restart?
Is there a yellow exclamation point next to your sound device or any other one.
Have you tried to update the drivers for the sound card?

I changed the pci slot for soundcard and the yellow exclamation thingy disappaered but still no sound.

Do you have volume control icon in the system tray? check and see if it is muted.
Did the Code 12 error go away after changing to a different slot?
In device manager does it show the device is working properly and the proper driver installed? Click on your volume control and check sounds and audio devices properties
or open volume control and check options/properties then check playback to see what is checked

Click on your volume control and check sounds and audio devices properties
or open volume control and check options/properties then check playback to see what is checked.