I am looking for a computer case that will fit a vostro 220 slim tower's motherboard.
I think the motherboard is a G33M02 made by FoxConn. I think it is also called a p301d dell motherboard.
There are 4 screws for the heat sink that go through the motherboard and connect into the case.
Seems that your very practical minded, so let's keep it simple. My computer is on 24/7 365 and is used everyday for most of the day. Thereby one would need a simple case, no doors or bling to distract or impede daily activity. I also keep my computer off the floor and at a work level on top of my work station. Better cooling but does require almost silent operation. You will decide what works best for you. With all of this in mind, take a look at the Gigabyte Triton 180 case on newegg and see if that may meet your needs. Have fun with it.
I'm not familiar with that setup, I might suggest changing the heatsink. The current system may be used with the old case only but not really necessary if you change out the case. Foxconn's support and list of compatibility components does not include heatsink(s). May be someone else on the forum is more familiar with that type of setup. In the event that you want to change the CPU heatsink and fan, I will suggest the Scythe Scang 1100 also found on newegg.
I'm a little late with this reply, but with regard to the heatsink, you have two choices...
If you already have the Dell heatsink, you can use it by just finding four nuts that fit the screws, and mounting it before you install the motherboard in the case. If you do this, be careful not to overtighten the screws!!
The second choice is to buy a standard heatsink. If you do this, make sure it has the standard cable/plug, and...
IMPORTANT----remove the four black fiber washers on BOTH SIDES of the motherboard. These are self-adhesive. Just make sure you don't nick or cut any of the traces on the motherboard.
Once you have removed ALL EIGHT washers, the click-in heatsink will fit perfectly.