Osobiscie powiem, ze ten Twoj sposob mi sie nie podoba, ale kwestia gustu 
To nie moj tylko taki wynalazłem
Jest jeszcze:
Environment.TickCount
ktore zwraca czas w milisekundach od startu systemu [czyli to wlasnie getTickCount() 
]
Zastosowałem to i w aplikacji windows ładnie śmiga ale na PPC nie działa
. Może bys mial ochote sie troche pobawic
? Ponizej kod do aplikacji windows.
using System;
using System.Drawing;
using System.Collections;
using System.ComponentModel;
using System.Windows.Forms;
using System.Data;
namespace timer2
{
/// <summary>
/// Summary description for Form1.
/// </summary>
public class Form1 : System.Windows.Forms.Form
{
private System.Windows.Forms.Label label1;
private System.Windows.Forms.Label label2;
private System.Windows.Forms.Timer timer1;
private System.ComponentModel.IContainer components;
private System.Windows.Forms.Button button1;
private System.Int32 CompTime;
public Form1()
{
//
// Required for Windows Form Designer support
//
InitializeComponent();
//
// TODO: Add any constructor code after InitializeComponent call
//
}
/// <summary>
/// Clean up any resources being used.
/// </summary>
protected override void Dispose( bool disposing )
{
if( disposing )
{
if (components != null)
{
components.Dispose();
}
}
base.Dispose( disposing );
}
#region Windows Form Designer generated code
/// <summary>
/// Required method for Designer support - do not modify
/// the contents of this method with the code editor.
/// </summary>
private void InitializeComponent()
{
this.components = new System.ComponentModel.Container();
this.label1 = new System.Windows.Forms.Label();
this.label2 = new System.Windows.Forms.Label();
this.timer1 = new System.Windows.Forms.Timer(this.components);
this.button1 = new System.Windows.Forms.Button();
this.SuspendLayout();
//
// label1
//
this.label1.Location = new System.Drawing.Point(16, 24);
this.label1.Name = "label1";
this.label1.Size = new System.Drawing.Size(504, 23);
this.label1.TabIndex = 0;
//
// label2
//
this.label2.Location = new System.Drawing.Point(16, 64);
this.label2.Name = "label2";
this.label2.Size = new System.Drawing.Size(504, 23);
this.label2.TabIndex = 1;
//
// timer1
//
this.timer1.Enabled = true;
this.timer1.Interval = 20;
this.timer1.Tick += new System.EventHandler(this.timer1_Tick);
//
// button1
//
this.button1.Location = new System.Drawing.Point(232, 112);
this.button1.Name = "button1";
this.button1.TabIndex = 2;
this.button1.Text = "Start";
this.button1.Click += new System.EventHandler(this.button1_Click);
//
// Form1
//
this.AutoScaleBaseSize = new System.Drawing.Size(5, 13);
this.ClientSize = new System.Drawing.Size(536, 157);
this.Controls.Add(this.button1);
this.Controls.Add(this.label2);
this.Controls.Add(this.label1);
this.Name = "Form1";
this.Text = "Timer";
this.Load += new System.EventHandler(this.Form1_Load);
this.ResumeLayout(false);
}
#endregion
/// <summary>
/// The main entry point for the application.
/// </summary>
[STAThread]
static void Main()
{
Application.Run(new Form1());
}
private void Form1_Load(object sender, System.EventArgs e)
{
}
private void timer1_Tick(object sender, System.EventArgs e)
{
long CurTickValue = Environment.TickCount;
long Difference = CurTickValue - CompTime;
long ComputerHours, ComputerMinutes, ComputerSeconds;
long ApplicationHours, ApplicationMinutes, ApplicationSeconds, Appset;
ComputerHours = (CurTickValue / (3600 * 999)) % 24;
ComputerMinutes = (CurTickValue / (60 * 999)) % 60;
ComputerSeconds = (CurTickValue / 999) % 60;
ApplicationHours = (Difference / (3600 * 999)) % 24;
ApplicationMinutes = (Difference / (60 * 999)) % 60;
ApplicationSeconds = (Difference / 999) % 60;
Appset = (Difference / 999) % 60;
label1.Text = String.Format("This computer has been ON for {0} hours, {1} minutes {2} seconds {3} milliseconds",
ComputerHours.ToString(),
ComputerMinutes.ToString(),
ComputerSeconds.ToString(),
CurTickValue.ToString() );
label2.Text = String.Format("This application has been running for {0} hours, {1} minutes {2} seconds {3} milliseconds",
ApplicationHours.ToString(),
ApplicationMinutes.ToString(),
ApplicationSeconds.ToString(),
Difference.ToString() );}
private void button1_Click(object sender, System.EventArgs e)
{
CompTime = Environment.TickCount;
}
}
}