Test.xaml

<Window x:Class="Computer_Support_Info.Test"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
        xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
        xmlns:local="clr-namespace:Computer_Support_Info"
        mc:Ignorable="d"
        Title="Test" Height="450" Width="800">
    <Grid>
        <DataGrid AutoGenerateColumns="False" HorizontalAlignment="Stretch">
            <DataGrid.Columns>
                <DataGridTextColumn Header="x" Binding="{Binding Name}" Width="1*" />
                <DataGridTextColumn Header="x" Binding="{Binding Value}" Width="9*" />
            </DataGrid.Columns>
            <local:NameAndValue Name="XX" Value="YYY"/>
        </DataGrid>

    </Grid>
</Window>