Windows Server 2008 unstable w/more than 4GB RAM

[birdus]

I have a Gigabyte ma790x-ud4p motherboard (latest BIOS—F-9). I can install Windows Server 2008 (R2, also) with only 4GB RAM and it runs fine. If I try to install the OS w/more than 4GB RAM, the install won't even finish—it hangs (but acts like it's going to finish—the progress bar just quits moving). If I add more sticks of RAM after the install is complete, the system is unstable. It reboots out of the blue and is just plain unstable.

Initially that was with an Athlon dual core 5200+ and Patriot memory (4 x 2GB). I looked on Gigabyte's Web site and bought memory that is approved for this motherboard—Kingston KVR800D2N6/4G (1.8V). With 1 of these sticks (4GB), same as before—everything works perfectly. Also same as before, if I put in more sticks, Windows won't even install.

What's even more interesting is that VMWare ESXi (a Linux-based OS) seems to install and run fine with more RAM (> 4GB).

What's going on here? Any ideas of what I can try? I'm trying to run this box as a virtual machine host, so I really do need the extra RAM (4x4GB). By the way, I'm also now running an Athlon quad-core CPU.

Thanks,
Jay

 

[GhislainG]

What timings and voltage? Does memtest86 run overnight without errors? If it wasn't stable with 8GB, it sure won't be any better with 16GB.

ESXi uses very little memory. Did you try to load enough VMs to use all 16GB of RAM?

 

[birdus]

Certainly more RAM won't improve things in and of itself, but the new RAM is certified by Gigabyte. I thought that might make a difference, although it probably shouldn't.

I'll throw all the RAM in there, then download and fire up memtest86. I'll report back with the results and with the timings and voltage.

Thanks,
Jay

 

[birdus]

The RAM is rated at 1.8V and CL=6. The BIOS is set for auto-everything, so it's not showing the voltage. If I got to manual, I can adjust the voltage +/- .1 V. I can only assume it's running at 1.8V. The timing is CAS#=6 (6-6-6-12), so at first glance that looks correct, but I can't be sure of all those numbers.

When I put all 4 sticks in (16GB), Windows hangs partway through the login process, so I won't be able to run any memory test programs.

Other ideas?

 

[GhislainG]

What do the SPD tables show in CPU-Z for 400 MHz? I find it weird that the timings are 6-6-6-12. I would expect them to be more like 6-6-6-18 or 6-6-6-24.

 

[birdus]

Oops. I'm sorry. You're right. They're 6-6-6-18.

SPD tables in CPU-Z for 400 MHz? You're going to need to break that down. Not sure what you mean.

 

[GhislainG]

Load CPU-Z. Then click the SPD tab. What are the JEDEC table values at 400 MHz (and other speeds if you want to provide them)? You could also check the Memory tab as that indicates the current settings (except for the voltage).

 

[birdus]

For 266MHz — 4.0, 4, 4, 12, 16, 1.8V
For 333MHz — 5.0, 5, 5, 15, 20, 1.8V
For 400MHz — 6.0, 6, 6, 18, 24, 1.8V

 

[GhislainG]

Are they set as per the SPD table in the BIOS? If so, increase the voltage a bit to see if it helps, but don't exceed 2.0V.

 

[birdus]

The readings in the BIOS are the same as in CPU-Z...6-6-6-18.

So, I added all the RAM back in, and...

I tried setting the DDR2 Voltage to 1.9V with the same result—Windows hung while booting.

I then tried setting the DDR2 Voltage to 2.0V. Same thing—Windows hung while starting.

Took all but 1 stick back out and set the voltage back to 1.8V. Awaiting further instructions.

 

[GhislainG]

You might not like my suggestion, but you should get a motherboard that is certified to work with those modules (if one exists). My first step would be to RMA the one that you have. Since the modules that you bought are on the QVL, then it should work. Since you tried 2 different CPUs with the same results, I presume that the issue isn't caused by the CPU. Regardless it will be challenging to get 16GB of RAM running properly on that platform. A 16GB server should normally be based on a Xeon or an Opteron, a server motherboard and server grade memory.

I run a few servers based on desktop motherboards with 8GB of RAM and they are stable. They are based on motherboards that are excellent for overclocking, but they are not overclocked to keep the systems stable.

 

[birdus]

Thanks for all your help, ChislainG. I'll look into replacing the motherboard then.

 

[GhislainG]

Which one will you select?

 

[birdus]

I have no idea. Do you have any suggestions? I don't want to spend a fortune. It's just for personal use at home. I would be willing to spend a couple hundred bucks. Mainly I just need a stable machine that will use my 16GB RAM and will run my Areca 1220 RAID card. Built-in Gigabit Ethernet would be nice. I have a video card, so that's not necessary.

Thanks again for all your help.

 

[GhislainG]

I know that quality P45 based motherboards can run 8GB (4 x 2GB) fine, but 16GB is more challenging. I own an Asus P5Q Deluxe that should be able to use G.Skill F2-6400CL6Q-16GBMQ (according to G.Skill and reviewers on Newegg). There are few reviews for your modules and only one runs 16GB on a MSI P45 Neo-3.