Does ram equal cache

[Bartjunited]

This is probably a really silly noon question but I'm Gonna ask it.

I use Genesis within xbmc to watch TV and movies and get an error of cache full once in a while and then I have to manually clear the cache.

Now my question is does cache equate to ram so the more ram I have the more cache it has to use.

This would influence whether I buy a box with 2g over 1g of ram.

Thanks in advance
Bart

[Bartjunited]

any thoughts anyone?