Java Swing JFrame inconsistent size

This is my first question on Stackoverflow. I have collected so many pages from here and have not solved my problem. My problem is sometimes (not always) the jframe I created does not show the same size with the size I set in the properties. I am using Netbeans 7.1.2 and only drag-and-drop to build a GUI. I can't code the GUI yet. This image, for example,

My window component appears to be clipped. Startup size and size in properties (minimum and preferred) are different. This has happened with both Free Design and Absolute Design. What is the problem? Do you know what a common problem is? I don't know what will happen. How can I solve this? I am sorry for the mistakes. Thank.

I don't know where the error is in the code, but this is that frame code:

@SuppressWarnings("unchecked")
// <editor-fold defaultstate="collapsed" desc="Generated Code">
private void initComponents() {

    jButton4 = new javax.swing.JButton();
    jSeparator1 = new javax.swing.JSeparator();
    btBack = new javax.swing.JButton();
    jButton5 = new javax.swing.JButton();
    jLabel1 = new javax.swing.JLabel();
    btNext = new javax.swing.JButton();
    jLabel10 = new javax.swing.JLabel();
    jLabel2 = new javax.swing.JLabel();
    jSeparator2 = new javax.swing.JSeparator();
    jLabel3 = new javax.swing.JLabel();
    jLabel4 = new javax.swing.JLabel();
    jLabel5 = new javax.swing.JLabel();
    jLabel6 = new javax.swing.JLabel();
    jLabel7 = new javax.swing.JLabel();
    lbJudul = new javax.swing.JLabel();
    jPanel1 = new javax.swing.JPanel();

    jButton4.setIcon(new javax.swing.ImageIcon(getClass().getResource("/otodidak/gambar/logomati.png"))); // NOI18N
    jButton4.setToolTipText("Tutup Otodidak");
    jButton4.addActionListener(new java.awt.event.ActionListener() {
        public void actionPerformed(java.awt.event.ActionEvent evt) {
            jButton4ActionPerformed(evt);
        }
    });

    setDefaultCloseOperation(javax.swing.WindowConstants.DISPOSE_ON_CLOSE);
    setTitle("Otodidak");
    setAlwaysOnTop(true);
    setLocationByPlatform(true);
    setPreferredSize(new java.awt.Dimension(787, 410));
    setResizable(false);
    getContentPane().setLayout(new org.netbeans.lib.awtextra.AbsoluteLayout());
    getContentPane().add(jSeparator1, new org.netbeans.lib.awtextra.AbsoluteConstraints(48, 53, 689, -1));

    btBack.setIcon(new javax.swing.ImageIcon(getClass().getResource("/otodidak/gambar/backlogo2.png"))); // NOI18N
    btBack.setToolTipText("Kembali");
    btBack.addMouseListener(new java.awt.event.MouseAdapter() {
        public void mouseClicked(java.awt.event.MouseEvent evt) {
            btBackMouseClicked(evt);
        }
    });
    btBack.addActionListener(new java.awt.event.ActionListener() {
        public void actionPerformed(java.awt.event.ActionEvent evt) {
            btBackActionPerformed(evt);
        }
    });
    getContentPane().add(btBack, new org.netbeans.lib.awtextra.AbsoluteConstraints(224, 340, 130, -1));

    jButton5.setIcon(new javax.swing.ImageIcon(getClass().getResource("/otodidak/gambar/logomati.png"))); // NOI18N
    jButton5.setToolTipText("Tutup Otodidak");
    jButton5.addActionListener(new java.awt.event.ActionListener() {
        public void actionPerformed(java.awt.event.ActionEvent evt) {
            jButton5ActionPerformed(evt);
        }
    });
    getContentPane().add(jButton5, new org.netbeans.lib.awtextra.AbsoluteConstraints(718, 358, 46, -1));

    jLabel1.setIcon(new javax.swing.ImageIcon(getClass().getResource("/otodidak/gambar/synapticwvdial.png"))); // NOI18N
    getContentPane().add(jLabel1, new org.netbeans.lib.awtextra.AbsoluteConstraints(388, 65, 348, 264));

    btNext.setIcon(new javax.swing.ImageIcon(getClass().getResource("/otodidak/gambar/nextlogo2.png"))); // NOI18N
    btNext.setToolTipText("Lanjut");
    btNext.addMouseListener(new java.awt.event.MouseAdapter() {
        public void mouseClicked(java.awt.event.MouseEvent evt) {
            btNextMouseClicked(evt);
        }
    });
    getContentPane().add(btNext, new org.netbeans.lib.awtextra.AbsoluteConstraints(396, 340, 130, 48));

    jLabel10.setFont(new java.awt.Font("Ubuntu", 1, 48)); // NOI18N
    jLabel10.setText("1");
    getContentPane().add(jLabel10, new org.netbeans.lib.awtextra.AbsoluteConstraints(48, 68, 36, 40));

    jLabel2.setFont(new java.awt.Font("Ubuntu", 0, 24)); // NOI18N
    jLabel2.setText("Instal Aplikasi wvdial");
    getContentPane().add(jLabel2, new org.netbeans.lib.awtextra.AbsoluteConstraints(90, 80, -1, 24));
    getContentPane().add(jSeparator2, new org.netbeans.lib.awtextra.AbsoluteConstraints(50, 116, 216, 18));

    jLabel3.setFont(new java.awt.Font("Ubuntu", 0, 16)); // NOI18N
    jLabel3.setText("1) Buka Synaptic.");
    getContentPane().add(jLabel3, new org.netbeans.lib.awtextra.AbsoluteConstraints(56, 132, 368, 26));

    jLabel4.setFont(new java.awt.Font("Ubuntu", 0, 16)); // NOI18N
    jLabel4.setText("3) Klik kanan wvdial, pilih mark for Installation. ");
    getContentPane().add(jLabel4, new org.netbeans.lib.awtextra.AbsoluteConstraints(56, 207, 346, -1));

    jLabel5.setFont(new java.awt.Font("Ubuntu", 0, 16)); // NOI18N
    jLabel5.setText("2) Ketik wvdial. ");
    getContentPane().add(jLabel5, new org.netbeans.lib.awtextra.AbsoluteConstraints(56, 170, 346, -1));

    jLabel6.setFont(new java.awt.Font("Ubuntu", 0, 16)); // NOI18N
    jLabel6.setText("4) Biarkan Synaptic menginstalkan wvdial. ");
    getContentPane().add(jLabel6, new org.netbeans.lib.awtextra.AbsoluteConstraints(56, 244, 346, -1));

    jLabel7.setFont(new java.awt.Font("Ubuntu", 0, 16)); // NOI18N
    jLabel7.setText("Catatan: internet harus menyala.");
    getContentPane().add(jLabel7, new org.netbeans.lib.awtextra.AbsoluteConstraints(58, 292, 298, 22));

    lbJudul.setFont(new java.awt.Font("Dialog", 1, 24)); // NOI18N
    lbJudul.setForeground(new java.awt.Color(254, 254, 254));
    lbJudul.setHorizontalAlignment(javax.swing.SwingConstants.CENTER);
    lbJudul.setText("Cara Menginstal Smartfren AC682");
    getContentPane().add(lbJudul, new org.netbeans.lib.awtextra.AbsoluteConstraints(117, 12, 578, -1));

    jPanel1.setBackground(new java.awt.Color(1, 1, 1));
    getContentPane().add(jPanel1, new org.netbeans.lib.awtextra.AbsoluteConstraints(0, -2, 788, 50));

    pack();

      

        
        
        
      

    

Not all code, but maybe useful. Thank you all for your attention ...