Tested my RAM, I have some questions.

[hamdrew]

I’ll try to make this as short as possible.

A little back-story: parents bought this computer in 2009. It came with a single stick of 512 MB DDR2 RAM running at 667 MHz. The motherboard only has 2 RAM slots, and the RAM has always been installed in the first slot.

I upgraded it recently, buying a new processor and 2 GBs of PNY DDR2 RAM running at 667 MHz.

I bought 2 GBs of cheap RAM before I bought the PNY RAM, but after crashing and blue screening a lot I sent it back.

A couple of days after testing the new RAM with Memtest86 (it came out fine, no errors) and installing it, I went to run Fallout: New Vegas, and my computer blue screened.

Running Memtest86 again, it came up with a lot of errors (don't remember how many exactly).

I decided today to run 12 different tests mixing and matching modules to see if I could find any patterns.

To distinguish the 2 PNY modules, I put a dot on one of the stickers. The old RAM so blue. I distinguish the 3 modules with the name Dot, Green, and Blue.

Here are my results, running each module 1 pass through Memtest86:

Dotted RAM:

1st slot: Pass, no errors.
2nd slot: Fail, 2580 errors (let this one run for 2 passes)

Green RAM:

1st slot: Pass, no errors.
2nd slot: Fail, 4070 errors.

Blue RAM (old):

1st slot: Pass, no errors.
2nd slot: Pass, no errors.

Next, I combined the RAM:

Dotted in the 1st slot, Green in the 2nd slot: Fail, 2110 errors.
Dotted in the 1st slot, Blue in the 2nd slot: Pass, no errors.
Green in the 1st slot, Dotted in the 2nd: Fail, 150 errors.
Green in the 1st slot, Blue in the 2nd slot: no errors.

The next 2 throw me off:

Blue in the 1st slot, Dotted in the 2nd slot: Pass, no errors.
Blue in the 1st slot, Green in the 2nd slot: Pass, no errors.

Is my 2nd RAM slot messed up after 4 years of not being used, or do the 2 PNY sticks not want to work dual-channeled? I thought it was the 2nd slot, but the blue RAM module working in the 2nd slot and the 2 green RAM modules working in the 2nd slot with the blue RAM in the 1st throw me off.

Can anyone explain what's going on? I'd appreciate it. I'll clear up any questions anyone has. I also took pictures of the failed tests if anyone needs them.

 

[Feldmarschall]

Are those 2GB PNY modules or 1GB modules?

 

[hamdrew]

Are those 2GB PNY modules or 1GB modules?

2x 1GB modules. I'm running Windows XP 32 bit.

 

[Feldmarschall]

Are those 2GB PNY modules or 1GB modules?

2x 1GB modules. I'm running Windows XP 32 bit.

What about your motherboard model?

 

[hamdrew]

Are those 2GB PNY modules or 1GB modules?

2x 1GB modules. I'm running Windows XP 32 bit.

What about your motherboard model?

It's an MSI 0A90. This machine is a pre-built HP, model dx2300.

 

[Feldmarschall]

I'm leaning towards motherboard incompatibiltiy with this memory altough it is on support list.

You have proved that dual channel works, proved that all three moduls work, only old works in dual channel. So, either mobo can't handle better latency on dual channel (if it's better) than old one or simply this particular ram can't be synched on that mobo.

It says on their site that they are fully compatible with HP. Only thing that crosses my mind before you RMA them is to reapply thermal paste on northbridge. It's a long shot but it may work.

 

[hamdrew]

I'm leaning towards motherboard incompatibiltiy with this memory altough it is on support list.

You have proved that dual channel works, proved that all three moduls work, only old works in dual channel. So, either mobo can't handle better latency on dual channel (if it's better) than old one or simply this particular ram can't be synched on that mobo.

It says on their site that they are fully compatible with HP. Only thing that crosses my mind before you RMA them is to reapply thermal paste on northbridge. It's a long shot but it may work.

I'm just going to keep them. Right now I've got it set up with one of the 1gb in slot 1 and the 512mb in slot 2.

 

[rojodogg]

2 * 240-pin DDR2 DIMM slots – DDR2 677/533 Dual Channel non-ECC, un-buffered memory
(Max 4GB) is what your MOBO supports.

Have youe done a drivers update? Check your bios and see what it says to make sure it has not changed the speeds of the RAM. I admit your problem is very strange. Have you checked to make sure you 2nd slot is free of dust or debry?