well it really depends on where they are located.
4 is pretty slim pickins... i would say you probably need at LEAST 5. but lets take a look.
FIRST AND FORMOST the back of the motherboard (mobo) should NEVER EVER touch the case. you will short circuit and fry something if it does.
so install memoryand CPU/Heatsink before you insert MoBo into case,
Be SURE you have enough support below your PCI(e) to install cards.
The rest is pretty simple. be sure to put 1 at the top left (as you look into case) and at the bottom left (so your PCI(e) slots line up and the I/O shield area will be stable and line up.
Here's what i would do if I were you...
get some small blocks of wood in the center area of your mobo (maybe even super clue them to the backing wall) and then put your 4 screws in each corner of the MoBo to keep it aligned.
Standoffs are pretty cheap mate, but still, I just fixed my Saturn's shift lever with 7 zip ties LOL.
Figure it out, just be SURE the MoBo solder points (the backside) do NOT touch the case!!!
When I placing standoffs in my case, I noticed I only got 4 standoffs, instead of 9.
Is it still okay to place it in the case with 5 missing standoffs or not? If not, what should I do?
i would email the case vendor for missing parts. before i did shot an email see if the case vendor placed them on the mb tray.some vendor do pre mount a few screws. if you have a local micro center or computer store you can pick up a full case screw kit for $10.00 that have extra of every case screw you could use.