If your CD bay covers are not full of holes for ventilation it will not help.
If you don't care about how it looks just take them out the rear fan(sure hope you have one) will do the rest.
If you have 3 CD rom slots free you can use a 120mm fan Scythe Kama Bay
you can also use hard drive coolers. there are some with an 80mm in 2 cd rom bays, but i cant find links right nows.