Non-ECC memory on Proliant DL385 g5

Solution 1:

The processors in the DL385G5 do not require ECC RAM, they do require Registered RAM (sometimes called "buffered" RAM). Finding Non-ECC Registered RAM is going to be difficult and expensive.

While it might technically work, it's going to cost much more than just using ECC Registered RAM.

Solution 2:

There's no reason not to use the proper RAM in the system. If you're simply concerned about cost, you're not looking in the right places. Used and third-party RAM is available for your ProLiant DL385 G5 at low prices.

Follow the quickspecs for the system...

Eight sockets for PC2-5300 DIMMs (DDR2-667) with Advanced ECC

You only have eight slots, but searching for one of the relevant SKU's will be your best bet... These are DIMM kits since that model requires RAM to be installed in pairs.

2GB DIMM - 408851-B21
4GB DIMM - 408853-B21
8GB DIMM - 408854-B21

Take those SKU's and head to eBay... Or search for 3rd-party RAM that is listed to be compatible with the SKU.