diff --git a/test/unit/test_allreduce.py b/test/unit/test_allreduce.py
index 2404408fe8..c45b28ab7f 100644
--- a/test/unit/test_allreduce.py
+++ b/test/unit/test_allreduce.py
@@ -6,7 +6,7 @@ from tinygrad.ops import Ops
 class TestRingAllReduce(unittest.TestCase):
   def test_schedule_ring(self):
     with Context(RING=2):
-      N = 6
+      N = 4
       ds = tuple(f"CPU:{i}" for i in range(N))
       t = Tensor.empty(N, N*100).shard(ds, axis=0).realize()
       schedules = t.sum(0).schedule_with_vars()[0]
@@ -17,5 +17,13 @@ class TestRingAllReduce(unittest.TestCase):
       # copy topology forms a ring
       self.assertEqual(len(set(pairs)), N)
 
+  def test_correct_ring(self):
+    with Context(RING=2):
+      N = 4
+      ds = tuple(f"CPU:{i}" for i in range(N))
+      t = Tensor.ones(N, N*100).contiguous().shard(ds, axis=0).realize()
+      out = t.sum(0)
+      self.assertListEqual(out.tolist(), [4]*N*100)
+
 if __name__ == '__main__':
   unittest.main()
diff --git a/tinygrad/ops.py b/tinygrad/ops.py
index 273545bb08..cb6dfd95de 100644
--- a/tinygrad/ops.py
+++ b/tinygrad/ops.py
@@ -114,7 +114,7 @@ class Ops(FastEnum):
   VALID = auto(); SPECIAL = auto(); NOOP = auto() # noqa: E702
 
   # reduce
-  REDUCE_AXIS = auto(); REDUCE = auto() # noqa: E702
+  REDUCE_AXIS = auto(); REDUCE = auto(); ALLREDUCE = auto() # noqa: E702
 
   # helper ops
   GEP = auto(); VECTORIZE = auto(); CAT = auto(); PTRCAT = auto() # noqa: E702
diff --git a/tinygrad/shape/view.py b/tinygrad/shape/view.py
index fbdea504c0..c93977410b 100644
--- a/tinygrad/shape/view.py
+++ b/tinygrad/shape/view.py
@@ -3,7 +3,7 @@ import functools, operator, itertools
 from dataclasses import dataclass
 from typing import Optional, cast, Sequence
 from tinygrad.dtype import dtypes
-from tinygrad.ops import resolve, UOp, Variable, sint, sym_infer, smax, smin, sint_to_uop
+from tinygrad.ops import resolve, UOp, Variable, sint, sym_infer, smax, smin, sint_to_uop, Ops
 from tinygrad.helpers import prod, all_int, argsort, flatten, ceildiv
 
 @functools.cache
@@ -107,7 +107,8 @@ class View:
   @staticmethod
   @functools.cache
   def create(shape:tuple[sint, ...], strides:Optional[tuple[sint, ...]]=None, offset:sint=0, mask:Optional[tuple[tuple[sint, sint], ...]]=None):
-    if not all(s >= 0 for s in shape): raise ValueError(f"Trying to create View with negative dimension: {shape=}")
+    # TODO: resolve shouldn't be needed here
+    if not all(resolve(s >= 0) for s in shape): raise ValueError(f"Trying to create View with negative dimension: {shape=}")
     strides = canonicalize_strides(shape, strides) if strides else strides_for_shape(shape)
     # canonicalize 0 in shape
     if 0 in shape: return View(shape, (0,) * len(shape), offset=0, mask=None, contiguous=True)
@@ -138,7 +139,7 @@ class View:
 
   @functools.cache  # pylint: disable=method-cache-max-size-none
   def unbind(self) -> tuple[View, dict[Variable, int]]:
-    var_unboundvar_val = [(v, v.unbind()) for v in self.vars()]
+    var_unboundvar_val = [(v, v.unbind()) for v in self.vars() if v.op is Ops.BIND]
     unbound_vars = {v:uv for v,(uv,_) in var_unboundvar_val}
     def substitute(x:sint): return x if isinstance(x, int) else x.substitute(unbound_vars)
     new_shape = tuple(map(substitute, self.shape))
@@ -196,8 +197,8 @@ class View:
           else: bad = True
           continue
         d1, s1 = term[0]
-        newb[d1] = max(newb[d1], ceildiv(b - o if s1 > 0 else e - o - 1, s1))
-        newe[d1] = min(newe[d1], (b - o if s1 < 0 else e - o - 1) // s1 + 1)
+        newb[d1] = smax(newb[d1], ceildiv(b - o if s1 > 0 else e - o - 1, s1))
+        newe[d1] = smin(newe[d1], (b - o if s1 < 0 else e - o - 1) // s1 + 1)
 
       # If any of vm1 was masked off, try again with that mask in place.
       if any((b, e) != (0, s) for b, e, s in zip(newb, newe, vm1.shape)):
diff --git a/tinygrad/spec.py b/tinygrad/spec.py
index 56a57f309d..0369651690 100644
--- a/tinygrad/spec.py
+++ b/tinygrad/spec.py
@@ -32,7 +32,8 @@ except (ImportError, AttributeError): z3_imported = False
 
 buffer_spec = PatternMatcher([
   (UPat(Ops.UNIQUE, dtypes.void, ()), lambda: True),
-  (UPat(Ops.DEVICE, dtypes.void, (), name="device"), lambda device: isinstance(device.arg, str)),
+  (UPat(Ops.DEVICE, dtypes.void, (), name="d"), lambda d:
+   isinstance(d.arg, str) or (isinstance(d.arg, tuple) and all(isinstance(s, str) for s in d.arg))),
   (UPat(Ops.BUFFER, src=(UPat(Ops.UNIQUE), UPat(Ops.DEVICE)), allow_any_len=True, name="buf"),
    lambda buf: isinstance(buf.arg, int) and isinstance(buf.dtype, (DType, ImageDType))),
   (UPat(Ops.BUFFER_VIEW, src=(UPat(Ops.BUFFER),), name="buf_view"),
@@ -75,8 +76,9 @@ tensor_uop_spec = buffer_spec+assign_spec+PatternMatcher([
   (UPat((Ops.DETACH, Ops.CONTIGUOUS, Ops.CONTIGUOUS_BACKWARD, Ops.FUSE), name="root", src=(UPat.var("x"),), arg=None),
    lambda root,x: root.dtype == x.dtype),
 
-  # COPY
+  # COPY/ALLREDUCE
   (UPat(Ops.COPY, name="copy", src=(UPat.var("x"), UPat(Ops.DEVICE))), lambda copy,x: copy.dtype == x.dtype),
+  (UPat(Ops.ALLREDUCE, name="red", src=(UPat.var("x"), UPat(Ops.DEVICE))), lambda red,x: red.dtype == x.dtype and isinstance(red.arg, Ops)),
 ])
 
 # ***** uop type spec *****
diff --git a/tinygrad/viz/serve.py b/tinygrad/viz/serve.py
index 58521f22bf..9305fca8bd 100755
--- a/tinygrad/viz/serve.py
+++ b/tinygrad/viz/serve.py
@@ -14,7 +14,8 @@ uops_colors = {Ops.LOAD: "#ffc0c0", Ops.STORE: "#87CEEB", Ops.CONST: "#e0e0e0",
                Ops.RANGE: "#c8a0e0", Ops.ASSIGN: "#909090", Ops.BARRIER: "#ff8080", Ops.IF: "#c8b0c0", Ops.SPECIAL: "#c0c0ff",
                Ops.INDEX: "#e8ffa0", Ops.WMMA: "#efefc0", Ops.VIEW: "#C8F9D4", Ops.MULTI: "#f6ccff", Ops.KERNEL: "#3e7f55", Ops.IGNORE: "#00C000",
                **{x:"#D8F9E4" for x in GroupOp.Movement}, **{x:"#ffffc0" for x in GroupOp.ALU}, Ops.THREEFRY:"#ffff80", Ops.BUFFER_VIEW: "#E5EAFF",
-               Ops.BLOCK: "#C4A484", Ops.BLOCKEND: "#C4A4A4", Ops.BUFFER: "#B0BDFF", Ops.COPY: "#a040a0", Ops.FUSE: "#FFa500"}
+               Ops.BLOCK: "#C4A484", Ops.BLOCKEND: "#C4A4A4", Ops.BUFFER: "#B0BDFF", Ops.COPY: "#a040a0", Ops.FUSE: "#FFa500",
+               Ops.ALLREDUCE: "#ff40a0"}
 
 # VIZ API