Im curious, does onboard RAID usually use ram for cache?

[dg]

These days, with many motherboards having RAID functions built in, I am
starting to wonder if they take advantage of system RAM for write back
caching. Has anybody heard anything about this?

Thanks,
--Dan

 

[Eric Gisin]

Not a good idea, it would only take away from the OS cache.

However, I think that is what Promise does with their write through/back
option. It makes benchmarks look better, at the expense of RAM usage.