Memory issue when using dbExpress

Question

I have to do some work on a legacy Delphi 7 application and wanted to switch from ADO components to dbExpress but it gives me a strange problem.

The setup is simple
when I use ADO I have this

ADOConnection
ADOQuery

DataSetProvider
ClientDataSet
DataSource
DBGrid

when executing a query that returns about 50000 rows there are no problems.
I can scroll to the last row, no problems occur

Now when I use dbExpress I have the following setup.
Note that I only switched the first 2 components, all the other remain unchanged.

SQLConnection
SQLQuery

DataSetProvider
ClientDataSet
DataSource
DBGrid

Executing the same query works, and it opens faster.
But I cannot scroll to the last row anymore, if I try to do that I get the error

Insufficient memory for this operation

In both cases I use the exact same code

ClientDataSet1.Open;

There are no events coupled to any of the components.
In fact I made a small test project with nothing in it but these components, and it still gives the same error. So its easy reproducable.

How is it possible that the ClientDataSet is able to hold all 50000 rows when using ADO, but not when using dbExpress ?
How can I get around this ?

As requested, here is the complete code of the sample project (I left out the persistent fields to keep it a bit smaller)

unit Unit1;

interface

uses
  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
  Dialogs, DB, DBClient, Provider, ADODB, StdCtrls, DBCtrls, Grids,
  DBGrids, ExtCtrls, DBXpress, FMTBcd, SqlExpr;

type
  TForm1 = class(TForm)
    Panel1: TPanel;
    DBGrid1: TDBGrid;
    DBNavigator1: TDBNavigator;
    Button1: TButton;
    Button2: TButton;
    DataSetProvider1: TDataSetProvider;
    ClientDataSet1: TClientDataSet;
    DataSource1: TDataSource;
    Label1: TLabel;
    SQLConnection1: TSQLConnection;
    SQLQuery1: TSQLQuery;
    procedure Button1Click(Sender: TObject);
    procedure Button2Click(Sender: TObject);
  private
  public
  end;

var
  Form1: TForm1;

implementation

{$R *.dfm}

procedure TForm1.Button1Click(Sender: TObject);
begin
  ClientDataSet1.Open;
end;

procedure TForm1.Button2Click(Sender: TObject);
begin
  ClientDataSet1.Close;
end;

end.

And the DFM (I left out the persistent fields to keep it a bit smaller)

object Form1: TForm1
  Left = 347
  Top = 125
  Width = 1305
  Height = 675
  Caption = 'Form1'
  Color = clBtnFace
  Font.Charset = DEFAULT_CHARSET
  Font.Color = clWindowText
  Font.Height = -11
  Font.Name = 'MS Sans Serif'
  Font.Style = []
  OldCreateOrder = False
  PixelsPerInch = 96
  TextHeight = 13
  object Panel1: TPanel
    Left = 0
    Top = 0
    Width = 1289
    Height = 97
    Align = alTop
    Caption = 'Panel1'
    TabOrder = 0
    object Label1: TLabel
      Left = 240
      Top = 32
      Width = 32
      Height = 13
      Caption = 'Label1'
    end
    object DBNavigator1: TDBNavigator
      Left = 16
      Top = 64
      Width = 240
      Height = 25
      DataSource = DataSource1
      TabOrder = 0
    end
    object Button1: TButton
      Left = 32
      Top = 24
      Width = 75
      Height = 25
      Caption = 'connect'
      TabOrder = 1
      OnClick = Button1Click
    end
    object Button2: TButton
      Left = 112
      Top = 24
      Width = 75
      Height = 25
      Caption = 'disconnect'
      TabOrder = 2
      OnClick = Button2Click
    end
  end
  object DBGrid1: TDBGrid
    Left = 0
    Top = 97
    Width = 1289
    Height = 539
    Align = alClient
    DataSource = DataSource1
    TabOrder = 1
    TitleFont.Charset = DEFAULT_CHARSET
    TitleFont.Color = clWindowText
    TitleFont.Height = -11
    TitleFont.Name = 'MS Sans Serif'
    TitleFont.Style = []
  end
  object DataSetProvider1: TDataSetProvider
    DataSet = SQLQuery1
    Left = 512
    Top = 328
  end
  object ClientDataSet1: TClientDataSet
    Aggregates = <>
    PacketRecords = 50
    Params = <>
    ProviderName = 'DataSetProvider1'
    Left = 512
    Top = 392
  end
  object DataSource1: TDataSource
    DataSet = ClientDataSet1
    Left = 528
    Top = 456
  end
  object SQLConnection1: TSQLConnection
    ConnectionName = 'MSSQLConnection'
    DriverName = 'MSSQL'
    GetDriverFunc = 'getSQLDriverMSSQL'
    LibraryName = 'dbexpmss.dll'
    LoginPrompt = False
    Params.Strings = (
      'DriverName=MSSQL'
      'HostName=XXXXXX'
      'DataBase=GTT_Test'
      'User_Name=XXX'
      'Password=XXX'
      'BlobSize=-1'
      'ErrorResourceFile='
      'LocaleCode=0000'
      'MSSQL TransIsolation=ReadCommited'
      'OS Authentication=False')
    VendorLib = 'oledb'
    Left = 584
    Top = 208
  end
  object SQLQuery1: TSQLQuery
    MaxBlobSize = -1
    Params = <>
    SQL.Strings = (
      'select * from vwRitComplete')
    SQLConnection = SQLConnection1
    Left = 584
    Top = 272
  end
end