MB Not Supporting Allowable RAM Amount

[XYZ]

Running an ABIT NF7-S Version 2.0 MB. Installed 3 1GB sticks of Crucial PC3200 RAM, per the application finder on their site, into an already running/stable machine. During normal Internet surfing use, I got a "blue screen of death", but with quite a bit of info listed on it; however, this screen would only show for ~1-2 seconds, so no way I could read everything it said. Right after this screen disappeared, the machine would reboot itself.

OK, so I got out the owner's manual, which stated that you should only run 2GB of RAM if it's PC3200. Reduced the amount to 2 GB, same deal, blue screen, immediate reboot. I now have it down to 1GB (1 512 MB & 2 256 MB sticks), and so far it's stable. The BIOS was updated last year to the last upgrade ABIT had, so that option is maxed out. Why would a machine not run in a stable manner even though you're using correct RAM, correctly installed, in correct amounts?

[The Wise Monkey]

After a quick Google search, I found this info:

3. Memory. Always use major brand-name memory (Crucial, OCZ, Mushkin, Corsair, Kingston). Always observe anti-static precautions when installing it. The NF7-S is fussy about which DIMM sockets the memory is installed in. The CD-ROM version of the User Manual states:

* Install DDR SDRAM modules in series from DIMM3 to DIMM1 sockets.
* When installing two PC3200 modules, install them in DIMM3 and DIMM2.

You won't find this in the hard copy of the User Manual and it is rather backwards from conventional logic. It does make a difference.

The default CMOS Setup memory timing settings are too fast for the memory most people would purchase for this motherboard. If left as they are, the motherboard will likely freeze-up randomly, if it works at all. Check you memory specifications and set them accordingly. The followings settings in the Advanced Chipset Features worked for the Crucial memory we installed:

Memory Timings

- Row-active delay 11

- RAS-to-CAS delay 3

- Row-precharge delay 3

- CAS latency time 2.5

The default CAS latency time of 2.0 will glitch most memory sold for PCs. The Row-active delay setting is a higher number than that specified for the memory we used and that of many other memory modules, but should result a faster system than the specified value.


So try this. :)

[XYZ]

Thank you for the reply. I changed the settings in the BIOS in the AM, and changed out the RAM in the PM after work. I placed 2 1GB sticks in the DIMM 2 and 3 slots. I have been using this computer all evening, and it has been nice and stable, no buggy behavior.

Reading back on the ABIT website for the archived BIOS updates, there were a couple of mentions of "enhanced memory compatibility", so knowing I already have the last updates, I may add a third 1GB stick into the last slot, and see if it's stable. Thanks again.

[The Wise Monkey]

Glad you got it sorted. :)

[XYZ]

I added the 3rd 1 GB stick of RAM earlier this evening, have been on the computer a good part of the night, and no instability. The computer recognizes the whole 3 GB in Device Manager. I am currently running the Prime 95 "torture test" that stresses RAM the most of any component, and so far so good :)

[The Wise Monkey]

Congrats - nice job. :)

[Amosmoses33]

I still get amazed by the knowledge around here. Great job WM helping him out.

[The Wise Monkey]

lol, ta - Google is your friend. :D