Motherboard and Windows detecting 8gb of RAM (2 Identical Sticks) yet only making 4gb Available

Hello, sorry to hear about your troubles...

This situation reminds me of a recent build I encountered within the last year. It is actually my brother's PC.

It was a socket LGA775 motherboard that used DDR3 RAM.

One of the sticks was a Kingston 4GB module. I decided to upgrade to 8GB, 2 x 4GB sticks. I purchased another 4GB stick of matching Kingston RAM with matching specifications. If I recall correctly, both sticks did show up in the BIOS, but by the time it got to Windows the computer would only recognize 4GB of RAM.

HOWEVER, upon calling Kingston and explaining the situation, it appeared as though they had changed the chips used on the module, even though they were matching sticks. Something along the lines of one stick using 256MB chips and the new stick using 512MB chips. Turns out it was either the motherboard that could not take the new module or that they were incompatible together, but I had to actually track down an older revision of that identical RAM!

From my experience, I am assuming one of the modules is either not compatible with the other, or that one of the modules is not fully compatible with that motherboard.

Hope that helps and good luck!

No problem, I'm going through my own computer headaches at the moment so can sympathize with the pains!

Yes they do appear to have the same number of chips on them. However, knowing the way these things work they still may have compatibility issues.

To be honest 4GB is a lot and should suffice in most circumstances. Even the recommended requirements for Black Flag only requires 4GB of RAM. If you have a stable 4GB, in my opinion it is more than enough at the moment. I used to run pretty intense games with skype video calls in the background on 4GB on pretty decent settings.

Also, my brother's PC has a last gen E8400 3GHz dual core CPU and we have played Battlefield 3 on great settings while skype chatting no problems whatsoever. Sometimes he even records his gameplay on top of that! In my opinion a 3GHz CPU is awesome and still has a lot of power to this day!

His PC worked that way even before upgrading the RAM as well, but it is nice to have that extra breathing room!

What happens when you just leave the Kingston 4GB in by itself? Does it detect it as 4GB in the BIOS and Windows? And would you have 4GB detected and 4GB usable with no errors?

If that is the case, I would suggest to just go with the Kingston for now. In it's current state it does appear to acknowledge that there is 8GB but only says that 2.96GB is usable. If it saw the Kingston as 4GB and was a usable 4GB then that seems like it would work better than it is in it's current state. And then when you have another matching module you could always test it to rule out that the RAM is the issue.

As far as your situation goes right now, it seems like a compatibility issue. Other than that, there could be other issues at play, which I don't even want to scare you with before you determine if the RAM is in fact the culprit!

Yes that makes sense then if you are using onboard video, that it is sharing 1GB (in this case with the physical RAM).

However, in that case you should still be up around ~7GB usable...

It could very well make sense that it wouldn't work in the B1 channel as some motherboards are designed to utilize a primary, in this case the A1 channel.

I would leave the timings and voltages set to auto at 1333MHz, 9-9-9-24 and 1.5 volts as recommended (please correct me if those are wrong).

Both sticks seem to share identical specifications but it definitely looks as though there is a conflict between them, they don't seem to want to communicate together properly.

The only way to really test that theory further is by putting an identical module in side by side to see how they operate.

Actually I just noticed looking over your pictures of the 2 different kinds of RAM...

The ADATA says on there that it is 4GB U-DIMM...

I believe the Kingston is a different kind, that would explain exactly why they would not be compatible together.

Actually found a link here with a similar situation:
http://www.computerforum.com/128782-dimm-udimm.html

The user does say that finding matching identical Kingston RAM modules did in fact fix the issue.

To be honest I do believe that is what will solve your problem!

Also, if not 100% sure, you could purchase locally and always return the module if they don't play nice together.

I hope all of this helps out and you get the full 8GB working!

By the way, Kingston is my favorite and the most reliable RAM for me

Until you do add another matching one, since they are not being recognized properly at the moment, my personal recommendation would be to remove the lesser of the 2 for now. Take out the ADATA and leave in the Kingston.

Yes, good luck to you, I believe it will work when you have the matching set. RAM seems to be very picky when it comes to working with other modules.

Both slots seem to be functioning properly, as both modules are recognized. Your main issue is the errors that seem to pop up when the two are installed in conjunction with each other, which is a fairly common problem with mismatched sets.

I also believe both modules are in good working condition, they just don't wanna work with each other! Maybe they are "prejudice"?!

But yeah, the Kingston RAM has a nice look to it, got the heat shields which serve a cosmetic and probably small operational purpose as well. I have always *knock on wood* had good experiences with that brand. The way it seems to go is that you either get a good piece and it lasts forever or you get a bad piece and its garbage right from the get go. That would also explain why they often have lifetime warranties.

One last piece of advice, maybe check out the program memtest86+ or prime95 after everything is all set up. They are programs to stress test the equipment to make sure it's stable. The reason I mention is because in my current troubles, I wish I would've done that in the beginning as it turns out now that I do indeed have some faulty hardware. The system worked pretty well up until recently where the problems became more often. Sometimes the faulty hardware slips by you because it does function to an extent not recognized right away. It's better to know if the hardware is stable right away to avoid troubles down the line.

Memtest86+ is easy to use and very safe, it will show if your system is having any errors communicating with the RAM. Be careful with Prime95 because it can really stress the hardware! In my case, there seems to be a faulty piece turning up errors with the RAM, however I believe the RAM is NOT faulty. Something many people would say is not common, but I do think it is more common than believed.

Anyways, good luck again, I wish you all the best and would be appreciative to hear that it all works out for you!

Actually to be honest that was just something that caught my eye, after looking more into it, it seems that it either might stand for unregistered or unbuffered.

I am pretty sure the Kingston would be just straight DIMM and unbuffered:
http://www.newegg.ca/Product/Product.aspx?Item=N82E16820104238
(sometimes I go to the Newegg website because they have pretty good specification sheets)

Here is a data sheet on the KHX1333C9D3B1/4G:
http://www.kingston.com/datasheets/KHX1333C9D3B1_4G.pdf

At the top left of the page it just calls it "DIMM"...

There may be someone more knowledgeable on the topic. It seems that while both UDIMM and DIMM will work on your motherboard, they maybe just don't work well together. However after doing some research, that part might not actually be as important as I first thought anyhow.

However, you should be able to rest assured that as long as the Kingston model / part number are the same for both modules (which I can see by your picture that they are) you should very well be alright!

In my situation where the two Kingston RAM modules were not compatible, it was because one was purchased a year or so ago, and then when I upgraded, the revision number of that model had changed. So basically in the time between, Kingston changed the design / structure of the RAM, they were 2 different revisions of the same RAM. I do believe that to be more of a rare case. That should not be the case for you as it seems as though you are acquiring them within a short time apart.

Wow, I am terribly sorry to hear about that my friend...

The only things that I am left to suggest to you would be:

1) Have you tried installing both the Kingston modules and clear the CMOS?

Usually there is a jumper on the board, it should mention in the manual where it is located with instructions. Make sure you turn off the power to the power supply on the back (if there is one) and / or unplug the power cord first. Usually you would just move the jumper over for like 10-30 seconds, while all power is disconnected, and then set the jumper back to original position. If it doesn't have a jumper and its only 2 prongs, you just short them with a screwdriver to complete the connection for 10 seconds and then let it go, while there is no power of course. Then you could reconnect, power up and reboot.

That would set all BIOS settings back to the default. I know it may be a pain setting it all up again, but sometimes clearing all the things that have been tinkered with and just booting as close to default settings as possible may enable them where one setting may be causing the troubles.

Try not even changing any BIOS settings at all once it has been reset just to see how far it gets.

2) If that fails, you mentioned that any one of these single sticks will work in the slot A1? You could try running memtest86+, the latest version, for about 3 hours per stick to determine if any of the sticks are faulty. Do each stick separate on it's own. You really should be concerned about the 2 Kingston modules primarily. Then if you want, check the ADATA one...

You can get the program here:
http://www.memtest.org/#downiso

It's very easy and straightforward to use. You can throw it on a blank CD and boot from that. Or get a spare USB flash stick you may have laying around and there is an auto-loader version that formats the USB stick and puts the image on for you. It will erase all data on the USB stick though.

Boot to the USB / CD and the program will start up on it's own and start testing the RAM. If you see any red / errors then the RAM is most likely faulty.

In some rare cases (like my current problem) it is not the fault of the RAM, it turned out to be the motherboard that was causing the RAM to appear faulty. To simplify and isolate the problem, I had resorted to even disconnecting everything unnecessary. Leaving just the motherboard, CPU and RAM connected directly to the power supply to conduct the most basic of testing without any other devices / disabling anything that may conflict.

Either way it's a good test to get out of the way so that you can proceed from there if need be.

3) I know we have covered most of these things, but here is an article straight from Microsoft in regards to the issue you are having:
http://support.microsoft.com/kb/978610

Maybe there is something that has been overlooked, in case you have not seen that article yet...

4) Last thing I can think of is that you could contact Kingston directly. Make sure you have the sticks in front of you with all the numbers and whatnot. They were very helpful with me in my previous issues and it was the reason that I even was able to solve the problem.

If all of the above fails, then I'm sorry to say there may be a deeper issue going on here. It could very well be a motherboard issue, maybe even power supply (which doesn't make as much sense seeing as how it does work fine with just one stick), or less likely another component.

I hope that is not the case and one of the above solutions does work for you. Good luck my friend and I'm sorry to not have been a greater help to you as of yet.

Yes well, I am glad to hear there may be a light at the end of the tunnel!

Sounds like a motherboard issue.

Sometimes it is difficult to diagnose because the system does work, but not perfectly. This was pretty much the same in my situation. I could even play a game like Payday 2 or Dead Island (which aren't super draining) for hours at a time. Then another day will turn on the computer, open the browser and crash! Leaves one very confused!

We must realize that the motherboard is one of the most complex parts in the system. It has got so many different components and is responsible for everything communicating properly. Not to mention the fact it contains the BIOS / software to translate communication between the devices and operating system to finally get to us in a readable fashion. It actually sometimes seems a miracle when they do work flawlessly!

Anyways I hope that resolves the issue and you are able to move forward and put the stress behind you! Good luck!