Do I Have Bad Parts?

[TimEwins]

Hi

 

I have just bought another 2G of RAM for my ABIT AW8-MAX based system.

 

The new parts are exactly the same as the old parts (but a years manufacturing gap), but the new parts don't work in my system :0(

 

I am using Corsair DDR2 TWINX 2GB PC6400 (2 x 1GB DIMMS)

 

I have set the divide ratio of my motherboard to 1:2 giving me a memory speed of DDR2-800.

 

The two old parts work at this speed (as the should as they are DDR2-800 rated) but the two new parts don't :0(

 

Do I have bad modules ?

 

For information, the modules I bought last year had to be exchanged for the same problem, but the replacements worked.

 

For Info, the older parts are version XMS6405v2.3, and thge newer parts XMS6405v6.2 ?

 

If they seem faulty then I will arrange an exchange with my supplier.

 

Regards

Tim

[Wired]

Have you tried the new sticks one at a time?

[TimEwins]

Yes, using one module the system won't boot at all, just sits at the POST screen, the other module gets into windows .... but blue screens?

[DerekT]

You will need to drop the throughput of the DRAM to have the onboard Northbridge/Memory Controller Hub respond stably with 4 DRAM banks. Dropping to 667Mhz should bring you back into stability.

 

Set one module in your DIMM 1.

 

Enter the BIOS.

 

OC Guru

 

Dram Frequency (CPU:DRAM) 4:5 or 667Mhz

 

Voltages Control

 

DDR SDRAM Voltage = 2.0v

MCH & PCI-e 1.5 Voltage = 1.55 - 1.6V

 

Advanced Chipset Features

 

DRAM Timing Selectable = Manual

CAS Latency Time = 5

RAS# to CAS# Delay = 5

RAS# to Precharge = 5

Precharge Delay (tRAS) = 12

 

Download memtest from http://www.memtest.org and extract the ISO image. Burn the ISO image to an CD-ROM disk. Boot to the optical drive with the memtest disk and allow for two full passes. Do this with all sticks singly. Then two in Dimm 1 & 3. Then the Second Set in Dimm 1 & 3. Finally test with all four sticks population all four DRAM banks.

 

Results?

[TimEwins]

Sorry for the delay ... but I have been away for the weekend, and its taken a while to get the results ....

 

Here they are:-

 

System set to DDR2-667 (3:5), FSB 200MHz

 

Old DIMM1, Slot1 - PASS (1GB)

Old DIMM2, Slot1 - PASS (1GB)

New DIMM1, Slot1 - PASS (1GB)

New DIMM2, Slot1 -PASS (1GB)

 

Old DIMM1+2, Slots1+3 - PASS (2GB)

New DIMM1+2, Slots!+3 - PASS (2GB)

 

Old DIMM1+2, Slots1+3, New DIMM1+2, Slots2+4 - PASS (4GB)

 

So I seem to have stability at DDR2-667.

 

I will do the same tests again at DDR2-800 just to see what happens.

 

I bought DDR2-800 RAM because I believed I could run it at this speed, to 'downgrade' to the more normal DDR2-667 bus speed is a bit disappointing, and indicates I should have bought lower grade parts in the first place.

 

Agreed its probably the Northbridge on my AW8-MAX that is causing the problem, but still disappointing.

 

I assume its better to have 4GB running reliably at DDR2-667 than 2GB running reliably at DDR2-800 ?

[DerekT]

I bought DDR2-800 RAM because I believed I could run it at this speed, to 'downgrade' to the more normal DDR2-667 bus speed is a bit disappointing, and indicates I should have bought lower grade parts in the first place.

 

Had you bought 667Mhz DRAM and populated all four DRAM banks, then you would have had to drop to 533Mhz so the lower grade parts would still have brought you lower performance than these ones. Had you bought 8500C5's then you would have had to drop to 6400 speeds.

 

Remove the two extra sticks and you are back up to 6400 speeds. This is across the board with both Intel and Nvidia chipsets.

 

I use productivity programs, video editing programs, high end gaming and I still use 2 X 1024 and have had no issues with any programs needing more DRAM or games needing more. I like the higher speed.

 

There are many higher end video/audio multiplexing programs, 3D modeling programs, astrological program, large graphics and database programs that will make use of the extra DRAM but most normal workstation programs do not make use of greater than the installed 2GB.

 

Test it. Set to 6400 and 2GB. Run your system. Use a digital stopwatch when running your programs. Documents load times, access times, save times, run times. Then move to 4 X 1024, drop the bandwidth and retest.

 

You will have your answer for your system.

 

As well, if you should overclock your CPU, you also overclock the Northbridge and this allows for greater throughput in the DRAM. If you decide you would like to try that route, the post in the Enthusiast section, link to this post and ask for help.