I searched the forums and could not find help for what might be causing this exception in my xamChart:

System.OverflowException
Message: "Value was either too large or too small for a Decimal."
Source: "mscorlib"
at System.Decimal..ctor(Double value)\r\n
at System.Convert.ToDecimal(Double value)\r\n
at Infragistics.Windows.Chart.AxisLabelsBase.FillLabels()\r\n
at Infragistics.Windows.Chart.ScenePane.CreateAxisLabels2D()\r\n
at Infragistics.Windows.Chart.ScenePane.Create2DScene()\r\n
at Infragistics.Windows.Chart.ScenePane.DrawWithException()\r\n
at Infragistics.Windows.Chart.ScenePane.Draw()\r\n
at Infragistics.Windows.Chart.ChartCreator.Create2DChart()\r\n
at Infragistics.Windows.Chart.Chart.RefreshWithException()\r\n
at Infragistics.Windows.Chart.Chart.Refresh()\r\n
at Infragistics.Windows.Chart.XamChart.Refresh()\r\n
at Infragistics.Windows.Chart.XamChart.RefreshProperty()\r\n

For  me, the cause was a Double.PositiveInfinity or Double.NegativeInfinity as a data point ValueY.

Perhaps this will help "the next guy."