diff -uprN -X dontdiff linux-2.6.4-clean/drivers/video/aty/radeon_base.c linux-2.6.4/drivers/video/aty/radeon_base.c
--- linux-2.6.4-clean/drivers/video/aty/radeon_base.c	2004-03-10 18:55:25.000000000 -0800
+++ linux-2.6.4/drivers/video/aty/radeon_base.c	2004-04-01 16:10:32.050172056 -0800
@@ -1144,6 +1144,7 @@ static void radeon_write_pll_regs(struct
 
 	/* Set PPLL ref. div */
 	if (rinfo->family == CHIP_FAMILY_R300 ||
+	    rinfo->family == CHIP_FAMILY_RS300 ||
 	    rinfo->family == CHIP_FAMILY_R350 ||
 	    rinfo->family == CHIP_FAMILY_RV350) {
 		if (mode->ppll_ref_div & R300_PPLL_REF_DIV_ACC_MASK) {
@@ -2129,7 +2130,31 @@ static int radeonfb_pci_register (struct
 #endif /* CONFIG_PPC_OF */
 
 	/* framebuffer size */
-	tmp = INREG(CONFIG_MEMSIZE);
+	if ((rinfo->family == CHIP_FAMILY_RS100) ||
+	    (rinfo->family == CHIP_FAMILY_RS200) ||
+	    (rinfo->family == CHIP_FAMILY_RS300)) {
+	  u32 tom = INREG(NB_TOM);
+	  tmp = ((((tom >> 16) - (tom & 0xffff) + 1) << 6) * 1024);
+
+	  OUTREG(MC_FB_LOCATION, tom);
+	  OUTREG(DISPLAY_BASE_ADDR, (tom & 0xffff) << 16);
+	  OUTREG(CRTC2_DISPLAY_BASE_ADDR, (tom & 0xffff) << 16);
+	  OUTREG(OV0_BASE_ADDR, (tom & 0xffff) << 16);
+
+	  /* This is supposed to fix the crtc2 noise problem. */
+	  OUTREG(GRPH2_BUFFER_CNTL, INREG(GRPH2_BUFFER_CNTL) & ~0x7f0000);
+ 
+	  if ((rinfo->family == CHIP_FAMILY_RS100) ||
+	      (rinfo->family == CHIP_FAMILY_RS200)) {
+            /* This is to workaround the asic bug for RMX, some versions
+               of BIOS dosen't have this register initialized correctly.
+            */
+            OUTREGP(CRTC_MORE_CNTL, CRTC_H_CUTOFF_ACTIVE_EN,
+                    ~CRTC_H_CUTOFF_ACTIVE_EN);
+	  }
+	} else {
+	  tmp = INREG(CONFIG_MEMSIZE);
+	}
 
 	/* mem size is bits [28:0], mask off the rest */
 	rinfo->video_ram = tmp & CONFIG_MEMSIZE_MASK;
diff -uprN -X dontdiff linux-2.6.4-clean/include/video/radeon.h linux-2.6.4/include/video/radeon.h
--- linux-2.6.4-clean/include/video/radeon.h	2004-03-10 18:55:54.000000000 -0800
+++ linux-2.6.4/include/video/radeon.h	2004-03-29 18:34:57.000000000 -0800
@@ -73,6 +73,7 @@
 #define MEM_IO_CNTL_A0                         0x0178  
 #define MEM_INIT_LATENCY_TIMER                 0x0154  
 #define MEM_SDRAM_MODE_REG                     0x0158  
+#define NB_TOM                                 0x015C  
 #define AGP_BASE                               0x0170  
 #define MEM_IO_CNTL_A1                         0x017C  
 #define MEM_IO_CNTL_B0                         0x0180
@@ -173,6 +174,8 @@
 #define CUR_CLR1                               0x0270  
 #define FP_HORZ_VERT_ACTIVE                    0x0278  
 #define CRTC_MORE_CNTL                         0x027C  
+#       define CRTC_H_CUTOFF_ACTIVE_EN         (1<<4)
+#       define CRTC_V_CUTOFF_ACTIVE_EN         (1<<5)
 #define DAC_EXT_CNTL                           0x0280  
 #define FP_GEN_CNTL                            0x0284  
 #define FP_HORZ_STRETCH                        0x028C  
@@ -185,6 +188,7 @@
 //#define DDA_ON_OFF			       0x02e4
 #define DVI_I2C_CNTL_1			       0x02e4
 #define GRPH_BUFFER_CNTL                       0x02F0
+#define GRPH2_BUFFER_CNTL                      0x03F0
 #define VGA_BUFFER_CNTL                        0x02F4
 #define OV0_Y_X_START                          0x0400
 #define OV0_Y_X_END                            0x0404