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darkrider01
04-25-05, 03:29 PM
I recently picked up some nice new DDR2 (see sig)(buy here) (http://www2.newegg.com/Product/Product.asp?Item=N82E16820220056) and I am confused about the timings. Patriot says that the timings should be 3-2-2-4 at PC4300(DDR2 533), 4-3-3-10 at PC5300(DDR2 667), 4-3-3-12 at PC5600(DDR2 700). My BIOS has more settings than info is given. In my BIOS, I have what is listed below. I would like to know what the other numbers are for my higher frequencies. I may have them completely wrong.......

Numbers in () are where I assume the supplied timings go (my current settings):

Cas Latency=(3)
Active to Precharge=4
RAS to CAS=(2)
RAS Precharge=(2)
Write Recovery=(4)
Refresh Cycle Time=28
Refresh Mode Select=7.8us

Also, CPU-Z reads my memory SPD timings as being able to be:

CAS Latency = 3
RAS To CAS = 2
RAS Precharge = 2
TRas = 3 (shouldn't this be 4?)

Did I set my timings wrong for DDR2-533? Thanks for reading my post and any help you may offer.

jAkUp
04-26-05, 02:05 AM
If you have no stability issues, then I would leave it where it is. (lower the number, the faster the performance)

Kickus_assius
04-26-05, 03:30 AM
Most ram will usually go slightly tighter than what it's rated at. The Tras can usually go lower, it's mainly the CAS latency that you have to be sure is set properly as it can cause non-booting and massive instability problems. I usually set everything to what the memory is rated at and leave the remaining settings on auto.

I wish I could run my memory at the proper speeds and timings. Damn A8V refuses to run my memory at DDR500 at all, let alone the 7-4-4-2.5 timings.

darkrider01
04-26-05, 10:29 AM
Would it be better to run the low timings at 2.8GHz or run relaxed timings at 3.3+GHz? That is probably the million dollar question. I will do all of the benchies if I could just figure out ALL of the correct timings to run my memory at when at higher frequencies. I would like to know what the following numbers should be when Patriot says 4-3-3-10....anyone have any ballpark numbers or rules of thumb?

Cas Latency=4
Active to Precharge=10 (right?)
RAS to CAS=3
RAS Precharge=3
Write Recovery=???
Refresh Cycle Time=???
Refresh Mode Select=7.8us or 15.6us???

Thanks again for any help.

darkrider01
04-28-05, 09:01 AM
No memory experts out there?

nVestor
04-28-05, 05:55 PM
No memory experts out there?
Apparently not... lol!

Check this out: http://www.anandtech.com/memory/showdoc.aspx?i=2112&p=1

The most amazing test results came from all the new DDR2 memories that we tested. Amazing, in that even the cheapest value DDR2 ran with complete stability at DDR2 667, which is the next major speed in the DDR2 highway. In addition, every one of the eight memories that we tested in this roundup ran with complete stability at the highest FSB which we could support on any current 925X motherboard - DDR2 686. Most of the tested DDR2 even accomplished this overclocking feat with much better than standard 4-4-4-10 timings and a modest voltage increase to 1.9V from the default 1.8V.

After this roundup, the message about DDR2 is very clear. As it exists today, DDR2 is much better than we expected it to be. Intel could easily move to DDR2 667 timings tomorrow and there would be a whole range of memories available to support that speed.
:cool:

darkrider01
05-04-05, 11:46 PM
Update:

I have tweaked my timings to their lowest (I guess). My current timings are as follows:

Cas Latency=3
Active to Precharge=4
RAS to CAS=2
RAS Precharge=2
Write Recovery=2
Refresh Cycle Time=8
Refresh Mode Select=7.8us

Funny that different programs read these timings differently. I am soo frickin confused.
Remember that these are DDR2 timings.....(cas-ras 2 cas-ras pre-cycle (tras))

Sisoft Sandra: (modules) 3-2-2-3 and (Chipset) 4-2-2-4 1CMD
PC Wizard:(modules) 3-1-1-2 and (chipset) 4-2-2-4
CPU-Z: (memory) 4-2-2-4 and (speed) 3-2-2-3