diff --git a/test/ops/test_index_sort.py b/test/ops/test_index_sort.py
index 91ee087cc..9dc04b0f7 100644
--- a/test/ops/test_index_sort.py
+++ b/test/ops/test_index_sort.py
@@ -10,7 +10,7 @@
 
 @pytest.mark.parametrize('device', DEVICES)
 def test_index_sort(device):
-    inputs = torch.randint(low=0, high=1024, size=(1000000, ), device=device)
+    inputs = torch.randperm(100_000, device=device)
     ref_sorted_input, ref_indices = torch.sort(inputs, stable=True)
     sorted_input, indices = pyg_lib.ops.index_sort(inputs)
     assert torch.all(ref_sorted_input == sorted_input)
diff --git a/test/ops/test_matmul.py b/test/ops/test_matmul.py
index 42a0ab91c..f630f4eda 100644
--- a/test/ops/test_matmul.py
+++ b/test/ops/test_matmul.py
@@ -75,7 +75,7 @@ def test_grouped_matmul_autograd(dtype, transposed, device):
     for i in range(len(outs)):
         assert outs[i].size() == (inputs[i].size(0), others[i].size(-1))
         expected = inputs[i] @ others[i] + biases[i]
-        assert torch.allclose(outs[i], expected, atol=1e-6)
+        assert torch.allclose(outs[i], expected, atol=1e-4)
 
     sum([out.sum() for out in outs]).backward()
     for i in range(len(outs)):