Solved Problems with ram or motherboard?

I bought a computer from HP a little over a year ago. At the same time, I bought a ram upgrade from another company. After a month or two, I started getting a lot of bluescreens and crashes, where about as soon as the computer would load up the desktop it would just crash again.

I ran a test on the ram and it found problems. I put the original ram that came from hp back in it and it worked fine and a test showed no problems.

I contacted the company I bought the ram from and they sent me a replacement stick of ram. I installed that, ran a test and it found no problems and it worked fine for a little over a year, until just recently.

I started getting the frequent bluescreens and constant crashes so I ran a test on the memory and it found a problem. I put back the original ram and it worked fine and a test showed no problems. The company sent me out another stick of ram.

I got that ram today and installed it and ran Windows Memory Diagnostics Tool and it found problems. For some reason I wanted to run more tests so after that I ran the Extensive Memory Test that comes as part of the bios on HP systems and it didn't find any problems. I decided to run the Windows memory tool again and that time it didn't find any problems.

Can the Windows Memory Diagnostics Tool give a false positive or does the fact it found problems the first time mean this new ram is bad?

I find it strange that I am having so much trouble with all these different sticks of ram from this company, where even this new stick of ram is having problems right away, and it is the third stick I have been through in a little over a year.

It makes me wonder if there is something wrong with the motherboard or ram slot but I haven't really heard much about that before. And then I remember that the original ram from HP never gives me any trouble. But how could one company send me so much bad ram?

The company will still replace the ram or give me a refund.

What do you think I should do and what do you make of this situation?

Well the first one only lasted about 1 or 2 months, the second one lasted about a year, and the third one I just got today, and seems to run ok, but I ran the Windows Memory Diagnostics Tool, just to check it out, and it said it found a problem with it. But I have ran that tool two other times since then and both times it said it didn't find a problem. So I'm not sure what to make of that. Would you replace that, or wait and see how it does?

The computer is HP Slim Desktop - S01-aF0134z

The HP Ram (according to the website for this computer) is 8 GB DDR4-2400 SDRAM, but when I look at the ram itself, it says 8GB PC4-3200AA (I don't know if that is the same thing or not.)

The first ram I bought I ordered myself, going by the hp motherboard specification site, which says this motherboard is TobaccoR3. They provide a link, but it is just for motherboard 'Tobacco'. I don't know if the 'R3' version is different or not.

Product Specifications:

According to the link for the motherboard specifications, it looks to me that it says it support up to PC4-19200(DDR4-2400), so when I ordered the ram I ordered DDR4 2400Mhz PC4-19200 1x 16 GB.

And that was what I got, the one that lasted only a month or so.

When I contacted the company about a replacement, they said they wanted to check to see if I had the best ram for the system so I gave them the link to my computer and they looked it up and said that it was close, but that there actually was a better ram I could use and they sent me DDR4-2666MHz PC4-21300 1x 16, and that is the one that lasted about a year (and also that is what this third one I just got is).

But when I look back now at the motherboard specifications, it doesn't seem to me like my motherboard should support that unless I am missing something or misunderstanding it. Of course it ran fine, nice and stable, for roughly a year (then suddenly had major issues). If it didn't support it, would it do that? Or would it run ok, but wear it out over time?

The company is ATech Components. Their customer service has been very responsive and quick to ship me new ram when I tell them my problems but I am still wondering what is going on though.

As for the Qualified Vendor List, I haven't checked it. I wanted to before I responded but I haven't been able to find it.

The computer is working ok with the new ram so far. I will be curious to see how long this new ram lasts. I'm really puzzled by the last two sticks not lasting very long, that seems really unusual to me, but maybe I just got unlucky.

Thank you Bruce and veeg for your comments; I really appreciate it and it was very helpful.

No, the warranty expired a little while back. With the ram not lasting long, I wondered if there was something with my system that could be destroying the ram. You mentioned the psu and motherboard. Is there anyway to test those for problems?

Sounds like a plan to me. Thanks for all your help and advice Bruce; I do appreciate it.