diff --git a/src/code/misc.lisp b/src/code/misc.lisp
index 50639d20346e214189c60f3786a94bf335164603..788a912fc45cc2697085289a4cf707b5ff857333 100644
--- a/src/code/misc.lisp
+++ b/src/code/misc.lisp
@@ -134,9 +134,6 @@
 
 
 ;;; Register various Lisp features
-#+pentium
-(sys:register-lisp-runtime-feature :pentium)
-
 #+sparc-v7
 (sys:register-lisp-runtime-feature :sparc-v7)
 
diff --git a/src/code/time.lisp b/src/code/time.lisp
index 999610add7895f4814782dc1a27c9880ba86719f..e6fb0c086bb586662e69daaf6e535b61f02dad72 100644
--- a/src/code/time.lisp
+++ b/src/code/time.lisp
@@ -283,11 +283,12 @@
 		       (system:get-system-info)
     (values user sys faults (get-bytes-consed))))
 
-#+(or pentium sparc-v9)
+#+(or x86 sparc-v9)
 (defun cycle-count/float ()
   (multiple-value-bind (lo hi)
       (vm::read-cycle-counter)
     (+ (* hi (expt 2.0d0 32)) lo)))
+
 #+ppc
 (progn
 (alien:def-alien-variable cycles-per-tick c-call:int)
@@ -300,7 +301,7 @@
     (* cycles-per-tick (+ (* hi (expt 2.0d0 32)) lo))))
 )
 
-#-(or pentium sparc-v9 ppc)
+#-(or x86 sparc-v9 ppc)
 (defun cycle-count/float () 0.0)
 
 (defvar *time-consing* nil)
diff --git a/src/compiler/x86/float.lisp b/src/compiler/x86/float.lisp
index e4d59524b4e7c4b6579f020d55e045252ae4e163..4d2ea5e1e8ca4f8ab8fcc48f15dee009636aca95 100644
--- a/src/compiler/x86/float.lisp
+++ b/src/compiler/x86/float.lisp
@@ -3302,8 +3302,7 @@
   (:arg-types double-float)
   (:result-types double-float)
   (:policy :fast-safe)
-  (:guard (or (not (backend-featurep :pentium))
-	      (not (backend-featurep :sse2))))
+  (:guard (not (backend-featurep :sse2)))
   (:note _N"inline log1p function")
   (:ignore temp)
   (:generator 5
@@ -3357,8 +3356,7 @@
   (:arg-types double-float)
   (:result-types double-float)
   (:policy :fast-safe)
-  (:guard (and (backend-featurep :pentium)
-	       (not (backend-featurep :sse2))))
+  (:guard (and (not (backend-featurep :sse2))))
   (:note _N"inline log1p with limited x range function")
   (:vop-var vop)
   (:save-p :compute-only)
diff --git a/src/compiler/x86/system.lisp b/src/compiler/x86/system.lisp
index 93519d8d21e889222eaf7b49a01859cd19bac3b2..71f7bb257d5332fdb9407e4809802e292b0aa7e0 100644
--- a/src/compiler/x86/system.lisp
+++ b/src/compiler/x86/system.lisp
@@ -590,7 +590,6 @@
 
 (define-vop (read-cycle-counter)
   (:translate read-cycle-counter)
-  (:guard (backend-featurep :pentium))
   (:args )
   (:policy :fast-safe)
   (:results (lo :scs (unsigned-reg))
@@ -614,7 +613,6 @@
     (move hi edx)
     (move lo eax)))
 
-#+pentium
 (defun read-cycle-counter ()
   (read-cycle-counter))