Need advice to upgrade Dell PowerEdge 2850

We have two Dell servers PowerEdge(TM) 2850.

Processor: Intel? Xeon? Processor 3.0GHz/2M, EM64T, 800MHz FSB
Memory: 1GB (2×512), DDR-2 400MHz ECC 1R

We would like to have an advise if we could use the standard Intel Xeon Processor DP3.0 GHz- FSB 800 MHz FROM INTEL and DDRAM 2 512 MB, Bus 400, PC 3200 Registered ECC FROM CRUCIAL to upgade these servers. My concern is the Dell hardware are tailored and OEM by Intel so the standard ones would not work.

Thanks in advance for your advice.