diff --git a/GpuMiner/Makefile b/GpuMiner/Makefile
index 4f53cfd..588e211 100644
--- a/GpuMiner/Makefile
+++ b/GpuMiner/Makefile
@@ -1,7 +1,10 @@
+TOP=$(shell readlink -f "$(dir $(lastword $(MAKEFILE_LIST)))")
+
 CC = g++ -O
 CPPFLAGS = -std=c++11 -I. -I/opt/AMDAPPSDK-3.0/include/
 LDFLAGS = -L/opt/AMDAPPSDK-3.0/lib/x86_64/sdk
 
+
 SRCS =                                  \
 	Core/CommonData.cpp                 \
 	Core/Farm.cpp                       \
@@ -41,3 +44,16 @@ xdag-gpu: main.o $(OBJS)
 	$(CC) -o xdag-gpu $(LDFLAGS) main.o $(OBJS) -lOpenCL -lpthread -lboost_system
 
 all: xdag-gpu
+
+.PHONY: clean
+clean:
+	rm -f $(TOP)/*.o
+	rm -f $(TOP)/Core/*.o
+	rm -f $(TOP)/Hash/*.o
+	rm -f $(TOP)/MinerEngine/*.o
+	rm -f $(TOP)/Utils/*.o
+	rm -f $(TOP)/XDagCore/*.o
+	rm -f $(TOP)/XDagCore/dar/*.o
+	rm -f $(TOP)/XDagCore/dfstool/*.o
+	rm -f $(TOP)/xdag-gpu
+
diff --git a/README.md b/README.md
index c74e5bc..97a3591 100644
--- a/README.md
+++ b/README.md
@@ -56,6 +56,14 @@ Check dependencies: libboost-dev, libboost-system-dev, openssl.
 
 Download this source code, then cd to source folder. In GpuMiner folder run command $make all, it will generate xdag-gpu.  
 
+note: for nvidia graphic card. may need more 2 steps:
+    
+    1) copy opencl header file to project. For example 
+        sudo cp -r /usr/local/cuda-10.0/targets/x86_64-linux/include/CL  ~/GpuMiner/CL
+    
+    2) install cuda-toolkit
+        sudo apt-get install nvidia-cuda-toolkit
+
 ### Launch parameters:
 
 	1) GPU benchmark: ./xdag-gpu -G -M