They are almost the same. Same chipset.  Same cpu/ram.  9020 is just a higher tier line than 7020 based on same architecture. [URL] [URL]
I am currently in process of buying a Dell Optiplex 7020 Mt. I have had great success in my 390 in terms of upgrading its RAM to 12GB and using an Nvidia 710 GT. I want to know what are sources I can look to for what the maximum/medium modifications I can put in my new pc. Questions that I haven't found a clear answer to. Does the motherboard control how much power the PSU delivers to each device? Because I heard there are limits on the power supply for Dell in some aspects, which wouldn't support a higher end card. Couldn't you just swap the PSU and be ok? Also, from what I have heard, the motherboard has limits of 16GB RAM, but Windows says it can support more on Professional. That leads me to think that it also has control of the power to each thing plugged into the power supply. And another thing, does it support any kind of i7 processors or ddr4 RAM? Sorry for the lengthy bit of questioning but gotta make sure I'm getting the right stuff.
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