I pulled the 512mb pc2 4200 that the toshiba a105-s1013 came with and put in a 1gb 5300 and it does not work in either slots...but when i put the 4200 back in along with the 5300, they both work. Is there any way to make the 1gb to run by itself? I actually have (2) 1gb sticks i am hoping to use.