Weird memory problem, 4x512, same specs/manufacturer

[MetalAges]

Hey there everyone.

I am having a weird memory issue (I think it is a memory issue?). I have an Abit IS7, support up to 4 GB. 4 memory slots. Computer recognizes 2 GB and running in Dual Channel mode.

I have been running 2x512 Crucial - unbuffered - non ECC - DDR Pc3200/400 CL3 for about a year or so now. I decided to add another gig so I bought the same Crucial memory. The new Crucial sticks I received from Newegg have the same exact specs but look a bit different (is this normal?). I popped them in, and ran fine for about 2 days. After the 2 days or so the computer started to reboot itself, lockup, you name it. I took out my old pair of memory and just left in the newer one, computer wigged out still. I figured bad memory. Sent it back and just got my new pair yesterday.

Well, when I woke up this morning and turned on my monitor (computer was running overnight) my computer had locked up. Rebooted, came up fine, fired up Battlefield 2, it locked up when I tried to join a game. As i type this (from the same computer running the 2 GB) it has been running for about 30 minutes. Here is the newest pair I got: http://www.crucial.com/store/MPartspecs.Asp?mtbpoid=354B5384A5CA7304&WSMD=IS7&WSPN=CT6464Z40B

Am I mssing something somewhere or could something else I have be weirding out with 2 GB?

Specs:
P4 3.0 HT Intel
Crucial memory 4x512
ATI x850pro
Raptor SATA drive
Audigy 2 ZS Platinum sound

Any help appreciated. I was so spoiled by those 2 days or running 2 GB , BF2 never ran so dreamy (as well as Photoshop!).

Deron

 

[kitchenshark]

With all 4 memory slots occupied, on many motherboards you have to reduce the memory speed to DDR333 in order to run in dual channel mode. Check the motherboard manual.

Also when you're checking the manual keep in mind that double sided and single sided memory modules (modules with chips on only one side or both) are different. There should be a matrix that shows the memory slots that can be occupied by what module and at what speed.

 

[MetalAges]

I checked my manual and it looks like is auto-adjusts as needed on the speeds. The manual says:

installing FOUR DIMM modules: Install DIMM modules of the same type and size for slots [DIMM1]+[DIMM3], and slots [DIMM2]+[DIMM4].
No hardware or BIOS setup required after adding or removing memory modules.

I have the correct modules in matching the guidelines above.

On your other note, that is the main difference on my newer memory, it has chips on both sides. The other sticks had it only on one side. Everything has the same specs though, would this still be a potential issue?

 

[kitchenshark]

Yes, that could be the issue. If your new ram has double side for the same 512 per strip, the memory 'density' is lower. Meaning taking more chips to make up the same amount of RAM. The internal circuitry is different so it could be the issue. Although the thing that puzzles me a bit still is why the restarts and lockups didn't clear up once you only had the new matched set in the MB.

Possibly the motherboard doesn't like the memory density for your new ram. Check to see if the ram falls under the memory compatibility chart of the manufacturer.

 

[MetalAges]

Yes the memory does fall under the compatible on the crucial memory chart.

Here's something interesting, I just opened up the computer to quazillion check some things haha.

The memory product numbers are the same, but one does have chips on both sides (new pair). But, what do these nubers mean?:

Old memory: CT6464Z40B.8T2
New memory: CT6464Z40B.16TG2

What are those numbers after the prodct number?

 

[kitchenshark]

Ack...

That 8T and 16T...it's been a looooong time, so don't remember exactly what they mean, but they ARE signifigant and mixing those numbers i seem to recall had issues. Let me see if I can find a link....

 

[kitchenshark]

Here you go...looks like this is a good thread for the issue.

http://www.pcguide.com/vb/archive/index.php/t-27448.html

Looks like to the 'x'T is referring to single or double sided. I still think there could be issues using the lower density ram. Hope someone else will jump in here and give a hand.

Hmmm...got to read that thread more now...maybe it doesn't help, sorry. I'm trying to think what's the issue...

In the meantime, one thought I had was to exchange 4 512's for 2 1Gb strips. Return the 512s and see about getting the 1gb stips. Wish I knew more to help more.

 

[MetalAges]

I appreciate your replies! I am going to pull out my old single sided memory and move over the double sided to see if that causes any issues. If so I am assuming there's some incompatibiity with it on the IS7 board. Weird weird.

 

[MetalAges]

So looks like the newer memory (double sided) runs fine on its own in my machine. My last test will be to add back my old ram but in the other slots than it was. Other than that, unless there's something I am missing, I guess the double sided vs. single just don't like to run together ?