After MOBO replaced cpu will only turn on with 1 stick of ram

[brownsox]

I see similar situations posted but here is mine:

Dell - Vostro 460 - Win 10 - (home office cpu use)

Had a MOBO failure.., replaced with Dell supplied new one.
Cpu will only attempt to start with 1 stick of ram (either original stick) installed in any of the 4 slots.
If I install the original 2 in the appropriate slots I get 4 error beeps and cpu will not start at all.
Checked for latest BIOS , all current drivers.., I am at a lost at this point.

Thanks for any suggestions.

 

[brownsox]

Well.., I decided to throw care to the wind and loaded the 2 sticks of RAM right next to each other which is the incorrect configuration. They should be in the same color slots 1 &3, or 2& 4.., well it all works now so I am running in 3&4 with my 2 sticks. cpu is showing the full amount of RAM. So sometimes a hammer and duct tape works especially with my Dell