Can't boot with both DIMMS

[Guest]

I have just received a new barebones PC with a Gigabyte GA-7VRXP mobo, and two 256MB PC2700 DIMMS from Corsair.

The machine will boot up and run just fine with either one of the two DIMMS installed, but if I try to use both of them I get no video and have to do a hard reset.

I have tried using CAS latencies of 2.5 and 2 and Command rates of 1T and 2T with no change in result.

Any ideas?

I am running bios version F4
The DIMMS are Corsair CM64SD256-2700CX2H

 

[Guest]

I managed to get both DIMMS working by setting the SDRAM frequency to 266 instead of 333 which is the default. I am now running with 512MB 266MHZ CAS 2 CR 1T.

I thought this was supposed to be 333MHZ RAM what's the deal?

-Steve

 

[Kidane]

Probably your processor can't handle 166 * whatever the multiplier is. You have to lower the multiplier unless you have an asynchronous memory bus (memory runs at different speed than CPU bus). In that case, I dunno. Is that motherboard a KT333?

Kidane


Det finns inget dåligt väder - bara dåliga kläder

 

[Guest]

Yes it is a KT333 based mobo. And the CPU is an Athlon XP 1900+ at 1.6GHZ.

-Steve

 

[Strife]

To my knowledge all KT333 motherboards have asynchronous memory bus. And no motherboard is going to automatically set the FSB higher than 133, it would damage people cpu's and they would get sued.

There is definately some bad chemistry between your memory and your motherboard. When the KT333 chipset was released there was no offical PC2700 standard or validation process so all the memory and motherboards are somewhat experimental. That is why there is currently no Crucial 2700, they waited until the standard was finalized to begin production.

JDEC recently revised the PC2700 standard to improve stability. None of the DIMM modules currently sold meet these new requirements.

Have you tried disabling bank interleaving? I hear this sometimes causes problems with some modules at high frequencies.

This is why I am planning on waiting a couple months before upgrading my system. Hopefully by then all the bug will be worked out.