diff --git a/src/agent_env/task_step/task_steps/deploy_sandbox.py b/src/agent_env/task_step/task_steps/deploy_sandbox.py
index 581e15b3..ae00fc47 100644
--- a/src/agent_env/task_step/task_steps/deploy_sandbox.py
+++ b/src/agent_env/task_step/task_steps/deploy_sandbox.py
@@ -31,7 +31,7 @@ def __init__(
         sandbox_name: str,
         sandbox_mode: str,
         image: Optional[str] = None,
-        cpu: float = 2.0,
+        cpu: float = 1.0,
         memory_mb: int = 8192,
         disk_size_gb: float = 10,
         ttl_seconds: int = TaskStep.DEFAULT_TTL_SECONDS,
@@ -88,7 +88,7 @@ def from_dict(cls, data: dict) -> DeploySandboxTaskStep:
             sandbox_name=data["sandbox_name"],
             sandbox_mode=data["sandbox_mode"],
             image=data.get("image"),
-            cpu=data.get("cpu", 2.0),
+            cpu=data.get("cpu", 1.0),
             memory_mb=data.get("memory_mb", 8192),
             disk_size_gb=data.get("disk_size_gb", 10),
             ttl_seconds=data.get("ttl_seconds", TaskStep.DEFAULT_TTL_SECONDS),
diff --git a/tst/unit/task_step/deploy_sandbox_default_cpu_test.py b/tst/unit/task_step/deploy_sandbox_default_cpu_test.py
new file mode 100644
index 00000000..cffa512d
--- /dev/null
+++ b/tst/unit/task_step/deploy_sandbox_default_cpu_test.py
@@ -0,0 +1,55 @@
+"""A deploy_sandbox step that sets no cpu reserves one vCPU, whether built in code or loaded from a stored dict, and
+a stored cpu is kept as written."""
+
+from unittest.mock import AsyncMock, patch
+
+import pytest
+
+from agent_env.providers.sandbox_providers.sandbox import NetworkPolicy
+from agent_env.task_step.context import TaskStepContext
+from agent_env.task_step.task_steps.deploy_sandbox import DeploySandboxTaskStep
+
+
+def _provider():
+    sandbox = AsyncMock()
+    sandbox.sandbox_id, sandbox.mode, sandbox.type = "sb-1", "vm", "modal_vm"
+    sandbox.tunnel_urls, sandbox.vnc_url, sandbox.network_policy = {}, None, NetworkPolicy()
+    provider = AsyncMock(ON_THIS_MACHINE=False)
+    provider.links = (provider,)
+    provider.create_vm.return_value = sandbox
+    provider.create_container.return_value = sandbox
+    return provider
+
+
+def _stored(**fields) -> dict:
+    return {"id": "s", "version": 1, "type": "deploy_sandbox", "sandbox_name": "box", "sandbox_mode": "vm", **fields}
+
+
+@pytest.mark.parametrize("step", [
+    DeploySandboxTaskStep(id="s", version=1, sandbox_name="box", sandbox_mode="vm"),
+    DeploySandboxTaskStep.from_dict(_stored()),
+], ids=["constructed", "from-dict"])
+def test_an_unsized_step_reserves_one_cpu(step):
+    assert step.cpu == 1.0
+
+
+def test_a_stored_cpu_is_kept():
+    assert DeploySandboxTaskStep.from_dict(_stored(cpu=2.0)).cpu == 2.0
+
+
+@pytest.mark.asyncio
+@pytest.mark.parametrize("mode, create, extra", [
+    ("vm", "create_vm", {}),
+    ("container", "create_container", {"image": "example.com/box:v1", "port": 80}),
+], ids=["vm", "container"])
+@pytest.mark.parametrize("step_cpu, requested", [(None, 1.0), (4.0, 4.0)], ids=["unsized", "sized"])
+async def test_the_provider_is_asked_for_the_steps_cpu(mode, create, extra, step_cpu, requested):
+    sized = {} if step_cpu is None else {"cpu": step_cpu}
+    step = DeploySandboxTaskStep(id="s", version=1, sandbox_name="box", sandbox_mode=mode, sandbox_type="any",
+                                 **sized, **extra)
+    provider = _provider()
+
+    with patch("agent_env.providers.sandbox_providers.sandbox_provider.build_sandbox_provider", return_value=provider):
+        await step.execute(TaskStepContext())
+
+    assert getattr(provider, create).call_args.kwargs["cpu"] == requested