sector size for ramdisk should be 512

src/etc/etc.alpha/disktab

@@ -1,4 +1,4 @@
-#	$OpenBSD: disktab,v 1.17 2007/06/16 18:14:14 deraadt Exp $
+#	$OpenBSD: disktab,v 1.18 2008/03/06 06:38:03 deraadt Exp $
 #	$NetBSD: disktab,v 1.2 1995/10/13 03:09:39 cgd Exp $
 
 # A DEC RZ25, configured so that all of the free partition IDs are at
@@ -23,7 +23,7 @@ rdroot:\
 
 # test if not having an 'a' works?
 OpenBSD2.1|Fake image for Bootable CDROM:\
-	:ty=winchester:se#2048:nt#1:rm#350:ns#160:nc#2048:\
+	:ty=winchester:se#512:nt#1:rm#350:ns#160:nc#2048:\
 	:pa#327680:oa#0:ba#8192:fa#1024:ta=ISO9660:\
 	:pc#327680:oc#0:bc#8192:fc#1024:tc=ISO9660:\