Bad Module

[chubien]

Hello,

 

I bought a matched pair of TWINX Platinum Series one year ago and have been using them reliably at 190 fsb (1:1) with a barton 2500 cpu (prime95 stable 10 hours). I recently built another similar computer (barton 2500 also) running on generic ram (3-4-4-8) at 217 fsb (1:1). Seing that the new system would overclock much nicer, I decided to use my corsair XMS3202 v1.2 CMX3200C2PT in the better computer to acheive maximum performance. To my surprise the new computer would only acheive 190 fsb (1:1) with the default timings (2.7v, 2.5-3-3-6) on the better corsair RAM. Obviously the 190 fsb limit on the old system, and now on the new system is memory related. I had always assumed that I had reached CPU limit at 190 fsb, I did not want to up the voltage as I was on stock cooling so left it at 190 fsb.

 

I proceeded to running on just one of the memory sticks, using any of the memory slots, using synched (1:1) or SPD (200 Mhz). One of the memory sticks will run just fine, at 1:1 at 200 Mhz, 2.7v, 2.5-3-3-6 and beyond (will actually acheive 208 fsb prime 95 stable). The other memory stick will boot windows at the same settings, but very unstable, will fail prime95 within seconds. And his regardless which memory slot, voltage, SPD or 1:1. Funny enought though it will run prime95 longer before posting errors with tighter timings (2-3-3-6). But it would still only do a best of 3-5 minutes before dying. I ran memtest overnight and it found no errors ... what gives !?

 

System1:

Mobo:MSI K7N2-ILSR (ultra400) BIOS 7.8

CPU:AMD Barton2500

Graphics: BFG-TI4200-128M

 

System2:

Mobo: MSI K7N2-LSR BIOS B30 (more stable than B40)

CPU: AMD Barton2500

Graphics: Sapphire 9600Pro 256M

 

Thanks for your help

[RAM GUY]

Please make sure that you have the latest BIOS for your MB and load Setup/Optimized default settings, and try the following BIOS settings;

TwinX1024 or TwinX512-3200C2

CPU Freq: 166 MHz (333 FSB)

System Performance: User Define

Memory Frequency: 100%

Resulting Frequency: 166 MHz (333 FSB)

Memory Timing: User Define

SDRAM CAS Latency: 2.5T

SDRAM RAS to CAS Delay (tRCD): 3T

SDRAM Row Precharge (tRP): 3T

SDRAM Active to Precharge Delay (tRAS): 6T

DDR Reference Voltage: 2.7 Volts

AGP Voltage: Default *unless you have ATI (9200 or 9600) or NVIDIA (5200 or 5700) then 1.6 Volts suggested!*

All other settings are motherboards defaults

Then please test them one at a time with http://www.memtest.org and let’s make sure it's not some other issue! I would run the test for at least 2-3 passes to be sure!

[chubien]

RAM GUY,

 

As stated in my original thread, I have the latest BIOS for system1 and I do not have the latest BIOS for system2 as it is unstable (I have had many discussions on the MSI forums about this).

My settings are identical to your recommendations except for the FSB setting. My CPU's are good to 200 FSB, my motherboards are good to 200 FSB, one memory stick is good to 200, but the other one isn't (please refer to original post for more details).

As stated earlier I ran memtest.exe and it showed no errors. But as per you recommendations I will run the other memory testing program "memtest86" overnight with the "bad stick" and see what gives.

 

Thanks

[RAM GUY]

N.P. Please keep us posted.

[chubien]

RAM GUY,

 

Ok, so ran memtest86 3.2 and memtest86+ 1.30 on the suspected bad module roughly for 2 hours each (they were both past pass4) and neither reported any errors with the 2.5-3-3-6 400 Mhz synched FSB (1:1).

But regardless this module will fail prime95 within SECONDS and kick me out of games when playing. I can only get prime95 stable at 190 FSB without errors or problems using the computer (system2). These errors are identical on system1, although I did not run memory tests on system1, assume it would also pass.

The other memory module runs prime95 rock solid, no errors (10 hours) and does not kick me out of games. Again this applies to system1 also.

What is the deal with memtest86 ? why ain't it picking up any errors !? Is this test truly reliable ? Prime95 seems to be speaking the truth here and not memtest86.

Bottom line is I cannot run this pair of modules together at 200 FSB ...

 

Any suggestions ?

 

thank you

[RAM GUY]

Have you gotten your Barton CPU to run 1:1 with the memory in a 200MHz speed? Since your CPU FSB is only 166MHz, and right now you are over clocking it, so I am not sure if you are aware of it; if you are please test the module with the default settings as stated on my previous post, maybe the processor is topping out at 200MHz.

[chubien]

The CPU is good to 217 FSB at 1.675v with low temps on load (40C <).

I have one Generic stick of memory that will run synched (1:1) at 217 FSB, I have one of the TWINX stick that runs at 208 FSB (1:1) and the other only manages 190 FSB (1:1). Note that all these figures are PRIME95 stable for 10 hours, anything above causes errors.

I know that the hardware is good to 200 FSB (CPU, Motherboard), the Barton 2500 I run in this computer is awesome and overclocks like crazy, with low voltage and rock solid. The bottleneck is that one faulty stick. Problem with this is I can't run the TWINX set at 200 FSB because of the bad stick .... (more details on original post)

[RAM GUY]

Please follow the link in my signature “I think I have a bad part!” and we will be happy to replace them or it!