Hi Dpearcepng,

Which form factor?

Optiplex 745
D6494 2GB, DDR2, 533MHz
KU354 2GB, DDR2, 667MHz
T8695 2GB, DDR2, 667MHz
YG410 2GB, DDR2, 800MHz

Optiplex 745c
T8695 2GB, DDR2, 667MHz

Optiplex 745e
D6494 2GB, DDR2, 533MHz
KU354 2GB, DDR2, 667MHz
T8695 2GB, DDR2, 667MHz

OK Chris, now I see that the first number is a Dell part number for a memory stick.

What I have seen in the forums, is that you can use two 2GB 800 Mhz sticks but not four. To use four sticks you have to use 667 Mhz sticks.

Is this accurate? Seems a little odd.

Dave

Thanks for the reply.

I have the mini-tower version. This memory limitation also seems to apply to the desktop and "small form" form factors.

Chris, thank you for this information.

Forgive my ignorance: Is the first set of numbers a motherboard part number?

Dave

If I want to go to 8 GB eventually or use 2 GB sticks, am I really limited to 667 Mhz memory?

I cannot find any Dell documentation that says yes or no to the question?

Well, based solely on Crucial saying it was compatible, I bought two sticks of 800Mhz 2 GB memory. Both the BIOS and Memtest + says it is running at 800 Mhz. So it looks like the comment I mentioned in my first post either was referring to a parts availability  issue or a HW issue that Dell fixed.