RE: Precision T3500 Ram
My Dell T3500 works with 8gb sticks with no issues.
Currently have Xeon 3565 and 8GB x 3 = 24Gb of none-ECC memory with the latest currently available BIOS.
I haven't tried installing more memory because as far as I know CPU I have doesn't support more that totally 24Gb of memory.
Will try to install more memory after upgrading CPU to Xeon 5600 family.