I would like to know if there are any motherboards with new chipsets
like SB750 on 790FX or 790GX
or ICH10R on P45 or Q45
that has integrated raid with cache memory.
Or any other less than $200-250 motherboards that has raid with dedicated memory.
I plan on using it to build a RAID5 fileserver with 5 * 1.5TB HDD.
I hope you didn't answered this question too many times by now at different intervals.
Most consumer grade boards don't have dedicated memory for RAID, the CPU and system memory do all the work. Your best bet would be to buy a RAID card. If you wanted it on the board you would have to look at server boards.