How Far Can You Upgrade a Dell Optiplex 745?

Hi all,

I have two Dell Optiplex 745 towers in the network, being used as Windows machines for the kids. I also purchased these for a very reasonable price on eBay - although the mini-tower versions of the Dell Optiplex range do seem to be a bit few and far between.

They are running Windows 7 Home Premium and they do so quite well. One of them is even running the 64 bit version and with the latest BIOS installed there were no issues with the hardware or getting drivers.

But how far can you push the hardware in terms of upgrades?

For CPU's that turns out to be easy (and disappointing!). The chipset is an Intel Q965 Express which has the following limitations:
1. FSB speed maximum of 1,066MHz
2. 65nm Core 2 Duo/Quad

In real terms, what does this mean?
1. Q6600 / QX6700 are the fastest (2.4GHz and 2.66GHz respectively) quad cores you can use.
2. E6700 is the fastest (2.6GHz) dual core that will work. I can also confirm that this works fine.

I can also confirm that an E7300 (1,066MHz FSB) does not work.

What about memory? Dell quotes that memory speeds can be from 400MHz, 533MHz to 800MHZ, but only supports 2GB DIMM's for 400/533MHz memory modules. I currently have 2GB modules in my machines and it works fine.
I am not sure about the maximum - it seems to vary from 4GB to 8GB depending on how fast the modules are.

And video cards? That's my latest frontier. At the moment I have a nVidia G210 in one of them and a nVidia GeForce 8400GS in the other. I want to try out a Radeon 5770 just to see if it works, but I might run into a problem with the slots and the power.

Stay tuned...