Problem with K7N2 mobo and DDR 400

[kingofspirals]

Hi new here...

I've just run into a weird issue with my motherboard and Memory.

K7N2 or K7N2G (they both look identical) 400 FSB edition.
AMD Athlon 2400+
300w PSU
2X 512mb DDR 400
Nvidia geforce fx 5500 128mb AGP

(Note: that Mobo, processor, memory and PSU are close to 5 years old)

To start, I will explain what has happened to my previously working setup.

I took out one of the DDR 400 memory sticks and put it in the Dimm 3 slot thinking it couldn't hurt anything. Little did I know....
I turn it on and it doesn't post. (black screen) So I say ok that doesn't work, so I put the memory back where it was functioning correctly. I turn it on, and it still doesn't post. So I say ok this isn't right... I then went through the standard procedure... power-off, cleared the cmos... and still no luck. I tried setting the other jumper to 100mhz safe mode, as opposed to 133mhz/166mhz normal mode. NO luck. so I think to myself... maybe I screwed up the memory. so I take both sticks out and put them in another "working" computer, and ta da! they both work.

Now this is where things get weird... I put the 512mb "DDR 333" memory that came from the working computer in the k7n2 motherboard and TA DA! the bios posted! now I'm thinking? what happened??? why is it working? so I switched the memory again, put the DDR 400 into the k7n2 and nothing.... doesn't post... now I remind you that the DDR 400 memory worked on this motherboard for a long time... no issues... and now suddenly its not working... but the memory seems to be in working order... the only diffrence between the two types of memory is the data rate 333 compared to 400.

this is where I really get confused... there doesn't seem to be anything wrong with the memory or the motherboard... the only thing I can think of is its maybe a PSU issue... but I don't have a PSU I can just swap out at the moment. IF any one can tell me what the issue might be please "elaborate".

[Xylon]

Try with one DDR 400 memory stick at time , now after start you not getting any thing on screen then problem is due to connection or motherboard processor .I had such problem when my processor was dead since you are not getting any beep looks like no issues with ram

[Jannat]

I have search on the Internet related to this issue, and found that mobo K7N2 already has memory issue, I have found this solution on the internet I will suggest you to try removing the battery for about 15 minutes & clearing the CMOS put back the battery & then move the jumper to safe mode & see what happens.

[kingofspirals]

Try with one DDR 400 memory stick at time , now after start you not getting any thing on screen then problem is due to connection or motherboard processor .I had such problem when my processor was dead since you are not getting any beep looks like no issues with ram

well I did try each one at a time, I tried many things. the processor seems fine, the computer post and loads the bios when I use the DDR 333... My mother board lacks a speaker so there's no beeps. But its just very strange that the memory stopped working in combo with this motherboard...

Jannat

I am interested in what you've found please post a link! I will try what you've suggested I haven't tried taking out the cmos battery yet. though I did try leaving it unplugged all night, after giving up... hoping it would work in the morning.

If there's a serious issue I may end up having to scrap the thing... but not if I can help it though... The issue may be that the parts are just starting to fail or something... the three things I can think of first hand are PSU, mobo or memory.... will see... keep posting...

another thought: maybe they have a newer bios version that has a fix for this... maybe flashing the bios is in order?

[kingofspirals]

no dice.... tried and failed....

[kingofspirals]

w00t! I managed to get the computer to post with both DRR 400 ram... After unplugging the floppy drive, CD drive, and all the fans, I'm thinking its a PSU issue... I'm guessing its just time I got new one given its age... get a 400w maybe that will fix it...

I'm going to plug everything back in and see if it still works... I'm guessing the DDR 333 worked because its voltages were different.... huh never could of guessed...

If anyone has any further reflections, or suggestions, please comment...

[gygabite]

It is very important that before upgrading you must check out the specifications of the motherboard. Because many a time if you just add up a hardware it does not match the exact configuration. Like the K7N2 mobo has 8x AGP port and blue ACR slot. The board has 3 DIMM slot which only supports upto 3GB of RAM. The RAM type can be C1600/2100/2700/3200 memory. If you are trying to add up more or other than this listed specification then your system would not boot up.

[kingofspirals]

Thanks for the reminder... I happen to agree that making sure the motherboard is compatible with the parts your trying to install is very important, and if your trying to lets say "use PC4200 memory" on this specific motherboard its not going to post...

But in this specific case All the parts I am working with are supported by the motherboard. I'm quickly finding out that, this specific motherboard is very touchy about memory... I've been working out the kinks and I've been able to get my original configuration to "work" but I'm running into issues I've never run into before. Like I've been able to get one stick working stable... but I'm now having problems with the second one... when I run the bios memory test it freezes around 700000kb - 950000kb and I am forced to turn off the computer. I've even had times when the second stick isn't even showing it being there... I'm starting to think this second stick is the source of these issues... Given its age I wouldn't be surprised if its gone bad... OR its an issue with the connection and the slot on the mobo, I find its a little loose and sometimes if I jiggle it the bios sees it again...

I'm thinking I'm going to upgrade to 2x 1gb DDR400 pc3200... and also while I'm at it I think I'm going to upgrade and CPU as well to 3200+ the k7n2 mobo I have is the 400 FSB version so it should be compatible. I honestly think I'd be better off replacing the entire computer with newer parts but I'm tight on cash so...

What would you recommend? Is there anything else you think might be contributing to these issues? If so I am welcoming any suggestions or tips... I really want to make sure my system is stable and stays that way...