Video Ram question

Neubie · 07-02-2006, 09:06 PM

I have a question for homework and I am not quite sure how to answer it. I am not a computer major and I would appreciate any help.

"I have 512 MB of memory. My monitor runs at 1600 x 1200 resolution, at 32-bit colour
depth. What percentage of my main memory is devoted to video RAM?"

How do I go about solving this? Thanks in advance!

Wim Sturkenboom · 07-02-2006, 11:30 PM

32 bit color depth, so each pixel uses 32 bits

Calculate the number of pixels.
From there, calculate the number of bits.
You need to know that 8 bits form a byte, so divide result by 8.
Calculate percentage.

Electro · 07-03-2006, 02:02 AM

There is no such thing as 32-bit color depth. There is only 24-bit color depth. The extra 8-bits is the alpha channel which is the opaque channel. The alpha channel provides the effect that program windows can be seen right through to the other windows. In Linux this channel is handled by the Composite module.

A 1600x1200 at 24-bit color depth takes about 6 MB of video RAM.

http://en.wikipedia.org/wiki/Video_Graphics_Array
http://www.computerhope.com/help/video.htm
http://en.wikipedia.org/wiki/Color_depth
http://en.wikipedia.org/wiki/Alpha_blending

Wim Sturkenboom · 07-03-2006, 04:17 AM

Thanks, always wondered what these extra 8 bits were for.

Neubie · 07-03-2006, 06:42 AM

Thanks Wim Sturkenboom and Electro for your help. I was heading actually thinking about doing it the way you guys mentioned, but I didn't know if I was correct. I guess it was an easy question for you guys. Not so easy for me since I'm just a