memory incompatibility ?

[danaradu]

Hi. I just purchased some memory yesterday - a dual channel kit (2x256) OCZ DUAL DDR PC-3200 Performance Series Rev. 3 Dual Channel, 512MB, PC400. I installed it on my Dell Dimension 4600 (which already had 512M of RAM Dual
Channel).

Here is the report on my computer BEFORE installing the memory:
____________________________________________________________________________
System Info
Model : Dell Dimension 4600i
Chassis Type : Mini Tower
Operating System : Microsoft Windows XP Professional Service Pack 2 (Build 2600)

Processor
Number Of Processors : 1 Hyper-Threading Enabled
Type : Intel Pentium 4 3000 MHz
Processors Bus Speed : 800 MHz
Motherboard Manufacturer : Dell Computer Corp.
Model : 0F4491
Rev. Not Available
CPU Slot/Socket Type : mPGA-478
Chipset Vendor : Intel i865P/PE/G/i848P Rev. A2
Bios Manufacturer : Dell Computer Corporation
Bios Version : A09
Graphics Model : Intel ONBOARD 82865G/GV ONBOARD
Speed : Not Available

Memory
Total RAM Installed : 512 MB
Type : DDR DIMM PC3200
Used RAM Slots: 2 of 4

This PC currently has 512 MB of memory installed, and supports a maximum of 4096 MB. There are 4 memory slots on the motherboard, and 2 of them are empty. The maximum memory module supported by this system is 1024 megabytes. You can add up to 2 PC3200 DDR DIMM modules (choose from available sizes below). To maintain consistent memory performance, select memory with a CAS Latency (CL) of 3.0 clocks or lower.

Slot 1: Kingston 256MB PC3200 DDR K
Slot 2: Kingston 256MB PC3200 DDR K
Slot 3: EMPTY
Slot 4: EMPTY
Total RAM Installed : 512MB
Type : DDR DIMM PC3200
Used RAM Slots: 2 of 4
Memory Bus Frequency: 199 MHz
Memory Timings: 3.0-3-3-8
Number Of Processors : 1 Hyper-Threading Enabled
Type : Intel Pentium 4 3000 MHz
Package : mPGA-478
Manufacturer Codename : Northwood
Clock Speed : 2992 MHz
Clock Multiplier : 15.0
Front Side Bus (FSB) Speed : 800 MHz
L2 Cache Size : 512 KBytes
Stepping : D1
Trace Width : 0.13
Microcode : 21h
Instruction Sets : MMX, SSE, SSE2
__________________________________________________________________________

After installing the new memory, the system correctly reported a total of 1GB of RAM, but at a speed of 266Mhz INSTEAD OF 400. I took the new memory out, I rebooted, and the speed went back again to 400Mhz. I re-installed it, I rebooted again, and the speed went down again to 266 Mhz. I then tried the following - I took out the original memory and I installed ONLY the OCZ memory - the system reported 512 Mb at 333 Mhz. I switched back to the original memory, and my BIOS immediately reported 512 MB at 400Mhz, correct. I have no idea on what's happening, assuming that the stiks have not been mis-labeled by OCZ... Regarding the BIOS - this is a DELL BIOS, and it's VERY skinny ! The timing fields are read only, and in the memory section I can only change the AGP aperture, which is currently at 128. The computer is not even a year old.

I've been told that maybe it's because of the CL2 on the new OCZ memory (or is it 2.5 ?) instead of CL3 as on my current memory. But I don't understand.... acording to Kingston's site, for instance, putting a faster memory onto a system will not necessarily make the system faster, but it will definitely not hurt.

Thank you very much for any advice, Alex.

 

[BrentUnitedMem]

When you install 4 modules many cases the system clocks all the modules down to 266MHz for stability concerns; 4 modules are less stable than two.

The OCZ PC-3200 modules are most likely capable of PC-3200 (DDR-400) however, your DELL machine adjusts the memory speed as according to the SBD chip on the memory module- most DELLS do not allow you to change the latency manually. In your case, your DELL is running the modules at a lower speed.

You can use <A HREF="http://www.cpuid.org/download/cpu-z-130.zip" target="_new">CPU-Z</A> to determine the latency of your module under the memory section of the program.

Like you said, it's most likely a latency issue.

<font color=blue>******
<font color=green>"Believe nothing, no matter where you read it, or who said it, unless it agrees with your own reason and common sence." -The Buddha
<font color=blue>AIM BrentUnitedMem

 

[RichPLS]

Intel 865/875 chipsets I thought were more stable with 4-512 MB modules.
I have a 875 with 4-512MB and it is stable using 2-2-2-5 timings.

<pre><font color=red>°¤o,¸¸¸,o¤°`°¤o \\// o¤°`°¤o,¸¸¸,o¤°
And the sign says "You got to have a membership card to get inside" Huh
So I got me a pen and paper And I made up my own little sign</pre><p></font color=red>

 

[BrentUnitedMem]

Performance and stability are separate issues.

For 865/875 you get the best performance in dual channel usuing 4 double-sided DIMMS (DDR-400).

However, in single channel you get the best performance using 2 double-sided modules (DDR-400).

In terms of stability, 2 modules are more stable than 4.

Moreover, on this chipset, for DDR333 and DDR266 you get the best performance using 2 double-sided modules on either dual-chanel or single-channel.

<font color=blue>******
<font color=green>"Believe nothing, no matter where you read it, or who said it, unless it agrees with your own reason and common sence." -The Buddha
<font color=blue>AIM BrentUnitedMem