--- k-2.6.18-6-clim-amd64-bobm/arch/x86_64/kernel/pci-gart.c.orig	2008-08-13 08:53:33.000000000 -0600
+++ k-2.6.18-6-clim-amd64-bobm/arch/x86_64/kernel/pci-gart.c	2008-08-13 08:55:48.000000000 -0600
@@ -540,8 +540,9 @@ static __init int init_k8_gatt(struct ag
 		pci_write_config_dword(dev, 0x98, gatt_reg);
 		pci_read_config_dword(dev, 0x90, &ctl); 
 
-		ctl |= 1;
-		ctl &= ~((1<<4) | (1<<5));
+		ctl |= 1;	/* set GartEn */
+		ctl |= (1<<4);	/* set DisGartCpu */
+		ctl &= ~(1<<5); /* clear DisGartIO */
 
 		pci_write_config_dword(dev, 0x90, ctl); 
 	}