diff --git a/kernel/Kconfig b/kernel/Kconfig
index 54e0ccf1f2d897..0553161eca1ee7 100644
--- a/kernel/Kconfig
+++ b/kernel/Kconfig
@@ -245,8 +245,9 @@ if DYNAMIC_THREAD
 
 config DYNAMIC_THREAD_STACK_SIZE
 	int "Size of each pre-allocated thread stack"
-	default 1024 if !64BIT
-	default 2048 if 64BIT
+	default 4096 if X86
+	default 1024 if !X86 && !64BIT
+	default 2048 if !X86 && 64BIT
 	help
 	  Default stack size (in bytes) for dynamic threads.
 
diff --git a/tests/posix/common/boards/qemu_x86.conf b/tests/posix/common/boards/qemu_x86.conf
deleted file mode 100644
index 2fa43926ee48f8..00000000000000
--- a/tests/posix/common/boards/qemu_x86.conf
+++ /dev/null
@@ -1 +0,0 @@
-CONFIG_DYNAMIC_THREAD_STACK_SIZE=4096
diff --git a/tests/posix/common/boards/qemu_x86_64.conf b/tests/posix/common/boards/qemu_x86_64.conf
deleted file mode 100644
index 2fa43926ee48f8..00000000000000
--- a/tests/posix/common/boards/qemu_x86_64.conf
+++ /dev/null
@@ -1 +0,0 @@
-CONFIG_DYNAMIC_THREAD_STACK_SIZE=4096
diff --git a/tests/posix/common/boards/qemu_x86_tiny.conf b/tests/posix/common/boards/qemu_x86_tiny.conf
new file mode 100644
index 00000000000000..01506ce9f553c2
--- /dev/null
+++ b/tests/posix/common/boards/qemu_x86_tiny.conf
@@ -0,0 +1,16 @@
+# Copyright (c) 2021 Intel Corporation
+# SPDX-License-Identifier: Apache-2.0
+
+# The test is highly sensitive to size of kernel image.
+# However, specifying how many pages used by
+# the backing store must be done in build time.
+# So here we are, tuning this manually.
+CONFIG_BACKING_STORE_RAM_PAGES=12
+
+# The following is needed so that .text and following
+# sections are present in physical memory to test
+# using backing store for anonymous memory.
+CONFIG_KERNEL_VM_BASE=0x0
+CONFIG_LINKER_GENERIC_SECTIONS_PRESENT_AT_BOOT=y
+CONFIG_BACKING_STORE_RAM=y
+CONFIG_BACKING_STORE_QEMU_X86_TINY_FLASH=n
diff --git a/tests/posix/common/boards/qemu_x86_tiny.overlay b/tests/posix/common/boards/qemu_x86_tiny.overlay
new file mode 100644
index 00000000000000..f717f3ff7edc76
--- /dev/null
+++ b/tests/posix/common/boards/qemu_x86_tiny.overlay
@@ -0,0 +1,11 @@
+/*
+ * Copyright (c) 2024, Tenstorrent AI ULC
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+/ {
+	dram0: memory@0 {
+		reg = <0x100000 0x80000>;
+	};
+};