Memory Timing

[Boogmiestro]

I am trying to find the best timing for my memory, here is my system:

Athlon 2400+
Albatron KX600 pro
1x512mb DDR kingston PC2700
1x256mb DDR kingston PC2700
RADEON 9600PRO

Right now I have my memory set at 4-6-4, is there maybe a better timing I could set it at? It sets at default at
5-7-5, should I leave it at default?

 

[Nights_L]

less the numbers, faster is

 

[MrBurns]

Try to lower your timings. You can use 3DMark01SE to test the stability and performance of each timing you try, but when you found your final timing, you should use prime95 to make a real stability test. Run the program for at least 6 hours, better 24 hours.

AMD Athlon XP 2700+
Epox 8rda+
Thermaltake Volcano 7+
2x256 MB PC2700
Creative GeForce 4 Ti 4800 (4600 Chip)
Chieftech Case
WD 80GB/8MB HDD
16x48 DVD-ROM
20x10x32 Burner

 

[addiarmadar]

is both of these modules have the same timming defaults? Would have better luch when changing timmings if they are same brand and size.

F-DISK-Format-Reinstal DO DA!! DO DA!!

 

[darko21]

Re: less the numbers, faster is

I know with Nforce2 boards most people get better overall memory performance using "Tras 11" but he is not using an Nforce2 board. so Tras 11 would be usless in this case.

This brings us back to, less the numbers, faster is. This is what most people or hardware sites seem to claim, but I read this mushkin article which seems to contradict this therory.

Memory, in many ways is like a book, you can only read after opening a book to a certain page and paragraph within that particular page. The RAS Pulse Width is the time until a page can be closed again. Therefore, just by definition, the minimum tRAS must be the RAS-to-CAS delay plus the read latency (CAS delay). That is fine for FPM and EDO memory with their single word data transfers. With SDRAM, memory controllers started to output a chain of four consecutive quadwords on every access. With DDR, that number has increased to eight quadwords that effectively are two consecutive bursts of four.

Now imagine someone closes the book you are reading from in the middle of a sentence. Right in your face! And does it over and again. This is what happens if tRAS is set too short. So here is the really simple calculation: The second burst of four has at least to be initiated and prefetched into the output buffers (like you get a glimpse at the headline in a book) before you can close the page without losing all information. That means that the minimum tRAS would be tRCD+CAS latency + 2 cycles (to output the first burst of four and make way for the second burst in the output buffers).

Any tRAS setting lower tRCD + CAS + 2 cycles will allow the memory controller to close the page "in your face!" over and again and that will cause a performance hit because of a truncated transfer that needs to be repeated. Along with those hassles comes the self-explanatory risk for data corruption. That one is not a real problem as long as the system is kept running but in case it is shut down and the memory content is written back to the hard disk drive, the consequences can be catastrophic. For the drive, that is."

So in theory running 2-2-2-5 is slower than 2-2-2-6. The ideal timings according to Mushkin works out to be:

CAS+tRCD+2 = tRAS

Examples:

2 CAS + 2 tRCD + 2 = 6 (2-2-2-6)

2 CAS + 3 tRCD + 2 = 7 (2-3-3-7)

2.5 CAS + 3 tRCD + 2 = 7.5 (2.5-3-3-8) *Round up*

If I glanced at a spilt box of tooth picks on the floor, could I tell you how many are in the pile. Not a chance, But then again I don't have to buy my underware at Kmart.

 

[darko21]

Not according to Mushkin.

So in theory running 2-2-2-5 is slower than 2-2-2-6. The ideal timings according to Mushkin works out to be:

This means 2-2-2-6 is faster than 2-2-2-5 at least according to Mushkin.

I remember this topic being brought up on a different web site everyone was skeptical. So people ran SiSoftware memory benchmark (using athlonxp) people compared both using 2-2-2-6 and 2-2-2-5 generally (I think every in every case) 2-2-2-6 scored higher than 2-2-2-5

Re read my previous post I think it explains it rather well.

If I glanced at a spilt box of tooth picks on the floor, could I tell you how many are in the pile. Not a chance, But then again I don't have to buy my underware at Kmart.