mem confusion!

[Guest Iceman]

Is my mem or cpu holding me back?

 

I pass mem test at 255 2-2-2-8 for 16 hrs and test #5 for 2 hrs but my computer only passes prime 95 for 12 hrs @250x10=2500mhz IF i put it in a 9/10 divider 180 so i don't get this what is holding me back or what is the problem?

 

Do i need to RMA the ram back?

[Surrept]

Your perfectly stable, memory is going to have errors no matter what your settings, it's just the nature of it, your trying to randomly access a grid thats trying to run systematicaly, somewhere along the lines your memory isn't going to be able to access what it needed.

[red930]

Your perfectly stable, memory is going to have errors no matter what your settings, it's just the nature of it,

 

I don't understand your statement, nor do I agree w/it

 

I also don't think there is anything wrong w/your ram

[Surrept]

I just read up some about ram and it's still sinking in but what I took from it is this. Random access memory is laid out in 2d grids, made of columns and rows, next these 2d grids are stacked ontop of eachother to form a 3d grid. When you access a certain section of memory it actives a particular bank. Once a bank is active it will make a data exchange. Once that exchange is finished the bank is set to refresh while another bank becomes active (this is memory interleave). The problem comes in when data needs to be retrieved consecutively from the same bank, this can cause a miss for data read/write. In the case of a miss with 1T (cpc on) I'm assumeing it results in an error. With 2T (cpc off) a bank that is being refreshed and is also called on then an extra wait state is added before attempting to activate the bank again. I would assume this prevents most errors. Another problem besides memory interleaving is that ram must be regularly refreshed or data will be lost, this can lead to the same problem esp if you have slow refreshing ram (or ram with large banks). So your left with a very systematic process of refreshing data combined with random access of memory, over 12 hours of running prime errors are to be expected.

[Guest Iceman]

ok what i meant that mem test 86 i can pass that @ 255 2-2-2-8 timings cpc enabled dram 1:1 200 but some how when i up the multy of the cpu prime fails!

i can pass prime on stock only!

[Surrept]

I don't quite get alot about the a64 but I find that if I ever get stuck somewhere it's best to start over at some stock settings and try a different approach to my clock, focus on a different aspect of the settings and always take it slow and be thorough.

[red930]

Have you read this,

http://www.dfi-street.com/forum/showthread.php?t=12960

[Surrept]

I read that over a few times and I still can't figure how most of it's used and what effects it would have, sort of how I didn't have a clue about memory timeings until I got a system to test everything on. I'll just have to muster up an a64 some time in the future to understand it