I am using a PIC18F45K20 with PLL clock multiplier to get a clock speed of 64Mhz which means i can execute instructions (4 cycles) at 16MHz. Right now I am toggling the R signal line for the vga at a frequency of 8MHz. Basically I have a screen with vertical red lines separated by black lines. The problem is I am noticing a jittering of the vertical pixel lines. The weirder part is that 1 out of every 3 vertical lines jitters a lot while the other two barely jitter. Could this be clock instability? I have had this problem for awhile and I am not sure how to fix it. My source code is too large to put on this post so if you need it I can try to show it to you another way. Thanks