Question Monitor goes to sleep when I try to install more RAM

[allamerican02]

I have a HP Pavilion Desktop - 550-127c (64 bit) and I recently installed an additional stick of 8gb RAM (16 total now). When I did this the computer started up fine once, but then when I started it up again later, the screen went black and didn't acquire a VGA signal.

I read this might be caused by dust in the RAM slot, so I took the RAM out and blew the dust out, and reinserted the RAM. I started the computer up and it started up fine, and I confirmed through the computer software that 16 GB was indeed installed. However, later when I started my computer again, the screen couldn't acquire a VGA signal and went to sleep.

I've tried using one RAM stick and not the other, and I have tested both slots. Both RAM sticks and both RAM slots work fine, but it never works when I have BOTH RAM sticks installed. Any idea what is going on? Please let me know if I need to include part specifics. Thanks. Below is the RAM information.

Bank Locator
CHANNEL A
Device Locator
DIMM 2
Manufacturer
Samsung
Serial Number
9576C0F5
Part Number
M378B1G73EB0-YK0
Memory Size
8192 MB
Maximum Memory Speed
1600 MHz
Memory Type
DDR3
Type Detail
Synchronous, Unregistered, Unbuffered

Bank Locator
CHANNEL B
Device Locator
DIMM 4
Manufacturer
Samsung
Serial Number
9576C0F5
Part Number
M378B1G73EB0-YK0
Memory Size
8192 MB
Maximum Memory Speed
1600 MHz
Memory Type
DDR3
Type Detail
Synchronous, Unregistered, Unbuffered

 

[Nemesia]

They both work separately but not together and the reason is that mixing RAM when not bought in a KIT could lead to instability issues or simply doesn't work together. Even if both sticks are the same brand and model.

If you want to upgrade your RAM you should buy a 2x8GB KIT suported by your motherboard.

 

[allamerican02]

But these are two sticks of exactly the same Kind of ram from Samsung. Same exact part. The computer came with only one stick and we just bought another one. I don't understand why 2 sticks of RAM From the same manufacturer that are exactly the same will not work together.