my CD-RW drive fail  

what brands are you trying to write on? what brand is your cd-rw drive? i have had this problem as well sometimes - my old dvd-rw drive has had errors in writing on really cheap brands.

Graphics on a monitor are constrained by the pixel size. This
results in a jagged display with what is known as a stair step
effect. To address this issue, Anti-aliasing is used. For this
multiple samples on the same portion of image is done. This
provides better image quality.

Why does my CD-RW drive fail to write on some brands of
media, even though it’s operating within the speed range?
CD media are capable of handling only a certain range of
write speeds. If, for example, you write an 8x capable CD-R
disk at a higher rate of 10x, chances are that the disk may
get written correctly, but you might not be able to reliably
read it on some drives. There is an identification on all CD-R
media that specifies the type of material the disk is made up
of, its maximum write speed, etc. Your CD-RW drive has a
similar listing in its firmware that enables it to recognize
such CD-Rs and lets you write on them reliable at those
speeds. If you find that you CD-RW drive cannot write on a
certain brand or speed of CDs, you could try to update the
BIOS of your drive to solve the problem.

i think ive figured out what might help. If you use Nero to burn your cds then all you have to do is select the "find maximum speed" option - that way it does a test first to see what speed your cd can burn at - then when it actually does the writing you are ensured that it will not fail. A lot of my cd writing used to fail because my dvdwriter was way too fast for the cd until i started selecting this option.