Hello, First time posting here, i hope someone within these forums will be able to help me.

So, a couple of months ago i bought a custom computer (bought all parts then put it together myself), and i have been happy with it completly.

Specs:
Vista 64-Bit
CPU: AMD Phenom X4 9850 (2.5GHZ)
Graphics: ATI Radeon 4870 512MB
Ram: 2 GB of DDR2 PC8500
500 GB of Hard drive Space


Now nearly 2 months later, i have decided to add 2 more GB of Ram. So i ordered 2 more GB and received it today. Now at first, i have NO success with putting all 4 GB in. So i decide to try 3 for now. It gets to the windows loading bar, but it just stays loading and never goes past that screen. All attempts with 3GB after that resulted in the computer restarting just after i select "safe mode" or "start windows normally", or even "boot from last good configuration". So it doesnt even reach the Loading Screen. I have tried just the 2 new sticks by themselves, no problems. I have also tried 1 new stick and one old stick, and still no problems. I have tried all combinations of the slots for the ram, and it all works, as long as i don't have more than 2 GB of ram in at one time. In the Bios it does recognize that i have 3GB or 4GB of ram in, but it still will not boot, as it will just keep restarting before it gets to the windows load screen.

Can anyone help?

Thanks, OneBullet.

Ram is more controlled by the motherboard specs . What mobo do you have?

Also when buying/replacing ram sticks it is best to always buy what has proved to work in your system before...Don't switch up manufacturers or types of ram. Try to buy exact replacement sticks and try to buy in matched pairs.

The more mixed ram installed on a system the more issues will develope.

By mixed....different manufacturers, different speeds, different values as in a low cost value ram vs. a high cost ram from the same manufacturer.

Most likely your board does not support it. I just ran into that issue with a brand new laptop. Had vista pre-installed, dual core and over all good specs. But suprise won't support more than 2GB.

Update: Ok, so i got 3GB of ram working by changing a couple of bios settings. I changed my Ram voltage to 2.1, set my cas latency to 5 and i enabled unganged ram. This allowed me to boot with 3 GB of ram.

However whenever i turn my computer on with all 4 GB in, it just stalls before it even gets to the first screen. My computer parts start making noise, but it just stays at the black screen as if my monitor just turned on then froze.

My mobo is the: Asus M3A32-MVP Deluxe

The two Types of ram i have are:

(older ram)
OCZ Reaper Dual Channel 2048MB PC8500 DDR2 1066MHz Memory (2 x 1024MB) run at CL 5-5-5

and

(newer ram)
OLYMPUS Reaper HPC 2GB (2 x 1GB) 240-Pin DDR2 SDRAM DDR2 1066 (PC2 8500) Dual Channel Kit Desktop Memory run at 5-5-5-15

I have tried 3GB at a time with both sticks of the new ram, but as long as i don't hit 4 GB i can boot.

Everything i can find out about this mobo says that it supports up to 8 GB of ram.. maybe im wrong though

Thanks for replys, hope you can help some more with these updates.

There are BIOS updates to fix memory incompatibilities.
which BIOS version do you have. Current is 1203.

You board supprots has crash free BIOS feature. Read the manual or website on how to update and use this feature if you have an older BIOS version.

Also
ASUSTeK Computer Inc.

ASUSTeK Computer Inc.-Support-

It would be best to look at their support website and find tested compatible memory and purchase four gigs of the same and sell what you have.