diff --git a/source/Cosmos.Core/GCImplementation.cs b/source/Cosmos.Core/GCImplementation.cs
index 1d462c214b..f9b83849d1 100644
--- a/source/Cosmos.Core/GCImplementation.cs
+++ b/source/Cosmos.Core/GCImplementation.cs
@@ -84,13 +84,6 @@ public static unsafe void Init()
             {
                 memPtr = (byte*)largestBlock->Address;
                 memLength = largestBlock->Length;
-                if ((uint)memPtr < CPU.GetEndOfKernel() + 1024)
-                {
-                    memPtr = (byte*)CPU.GetEndOfKernel() + 1024;
-                    memPtr += RAT.PageSize - (uint)memPtr % RAT.PageSize;
-                    memLength = largestBlock->Length - ((uint)memPtr - (uint)largestBlock->Address);
-                    memLength += RAT.PageSize - memLength % RAT.PageSize;
-                }
             }
             else
             {
diff --git a/source/Cosmos.Core/Memory/RAT.cs b/source/Cosmos.Core/Memory/RAT.cs
index b3cd764284..3413e3e687 100644
--- a/source/Cosmos.Core/Memory/RAT.cs
+++ b/source/Cosmos.Core/Memory/RAT.cs
@@ -157,6 +157,11 @@ public static void Init(byte* aStartPtr, uint aSize)
             uint xRatTotalSize = xRatPageCount * PageSize;
             mRAT = RamStart + RamSize - xRatTotalSize;
 
+            if (mRAT > HeapEnd)
+            {
+                throw new Exception("mRAT is greater than heap. rattotalsize is "+xRatTotalSize);
+            }
+
             // Mark empty pages as such in the RAT Table
             for (byte* p = mRAT; p < mRAT + TotalPageCount - xRatPageCount; p++)
             {
diff --git a/source/Cosmos.Core/Multiboot/Multiboot2.cs b/source/Cosmos.Core/Multiboot/Multiboot2.cs
index 421ae5fd45..76b3a2a4e0 100644
--- a/source/Cosmos.Core/Multiboot/Multiboot2.cs
+++ b/source/Cosmos.Core/Multiboot/Multiboot2.cs
@@ -21,7 +21,9 @@ public unsafe class Multiboot2
         public static bool IsVBEAvailable => Framebuffer->Address != 753664; // Some kinda default number.
         public static Framebuffer* Framebuffer { get; set; }
         public static MemoryMap* MemoryMap { get; set; }
-        public static EFI64* EFI64 { get; set; }
+        public static EFI64* EFI64 { get; set; }
+        public static AcpiOld* AcpiOld { get; set; }
+        public static AcpiNew* AcpiNew { get; set; }
 
         #endregion
 
@@ -59,6 +61,12 @@ public static void Init()
                             break;
                         case 12:
                             EFI64 = (EFI64*)Tag;
+                            break;
+                        case 14:
+                            AcpiOld = (AcpiOld*)Tag;
+                            break;
+                        case 15:
+                            AcpiNew = (AcpiNew*)Tag;
                             break;
                         default:
                             break;
diff --git a/source/Cosmos.Core/Multiboot/Tags/AcpiNew.cs b/source/Cosmos.Core/Multiboot/Tags/AcpiNew.cs
new file mode 100644
index 0000000000..3515112c35
--- /dev/null
+++ b/source/Cosmos.Core/Multiboot/Tags/AcpiNew.cs
@@ -0,0 +1,37 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Runtime.InteropServices;
+using System.Text;
+using System.Threading.Tasks;
+
+namespace Cosmos.Core.Multiboot.Tags
+{
+    /// <summary>
+    /// Tag AcpiOld
+    /// </summary>
+    [StructLayout(LayoutKind.Explicit, Size = 44)]
+    public unsafe readonly struct AcpiNew
+    {
+        [FieldOffset(0)]
+        public readonly uint Type;
+        [FieldOffset(4)]
+        public readonly uint Size;
+        [FieldOffset(8)]
+        public readonly ulong Signature;
+        [FieldOffset(16)]
+        public readonly byte Checksum;
+        [FieldOffset(17)]
+        public readonly uint OEMID;
+        [FieldOffset(23)]
+        public readonly byte Revision;
+        [FieldOffset(24)]
+        public readonly uint RsdtAddress;
+        [FieldOffset(28)]
+        public readonly uint Length;
+        [FieldOffset(32)]
+        public readonly ulong XsdtAddress;
+        [FieldOffset(40)]
+        public readonly byte ExtendedChecksum;
+    }
+}
diff --git a/source/Cosmos.Core/Multiboot/Tags/AcpiOld.cs b/source/Cosmos.Core/Multiboot/Tags/AcpiOld.cs
new file mode 100644
index 0000000000..a03a547c31
--- /dev/null
+++ b/source/Cosmos.Core/Multiboot/Tags/AcpiOld.cs
@@ -0,0 +1,31 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Runtime.InteropServices;
+using System.Text;
+using System.Threading.Tasks;
+
+namespace Cosmos.Core.Multiboot.Tags
+{
+    /// <summary>
+    /// Tag AcpiOld
+    /// </summary>
+    [StructLayout(LayoutKind.Explicit, Size = 28)]
+    public unsafe readonly struct AcpiOld
+    {
+        [FieldOffset(0)]
+        public readonly uint Type;
+        [FieldOffset(4)]
+        public readonly uint Size;
+        [FieldOffset(8)]
+        public readonly ulong Signature;
+        [FieldOffset(16)]
+        public readonly byte Checksum;
+        [FieldOffset(17)]
+        public readonly uint OEMID;
+        [FieldOffset(23)]
+        public readonly byte Revision;
+        [FieldOffset(24)]
+        public readonly uint RsdtAddress;
+    }
+}