Tightening memory timings

[wongnog]

hey guys. I've been testing some OCZ DDR Platinum Rev2 1GB(2x512M) PC3200 400MHZ 2-2-2-5 in my system (Asus A8N-SLI Premium with an Opteron 165). I've determined the highest HTT is 277 fsb with vcore 1.4, but the memory under the loosest timings can not go that high. Best I can get is around 240, so I'm running my system at 277x9 with a 5:6 memory divider. So right now memory is running at 226.63 Mhz under the following settings:

VDimm = 2.80 V
Cas latency (TCL) : 3
Min ras active time (TRAS) : 7
Ras to Cas delay (TRCD) : 4
Row precharge time (TRP) : 3
Row Cycle time (TRC) : 16
Row refresh cycle time (TRFC) :22
Read-to-write time (TRWT) : 4
Write recovery time (TWR) : 3
1T/2T memory timing : 2T
S/W Dram over 4gb remapping : Disabled
H/W Dram over 4gb remapping : Disabled

I've been told to try the following timings. But in what order should I begin changing the timings?

Cas latency (TCL) : 2
Min ras active time (TRAS) : 5
Ras to Cas delay (TRCD) : 3
Row precharge time (TRP) : 2
Row Cycle time (TRC) : 16
Row refresh cycle time (TRFC) :22
Read-to-write time (TRWT) : 3
Write recovery time (TWR) : 3
1T/2T memory timing : 1T

 

[myocardia]

That RAM won't do 226 Mhz at 2-3-2-5 timings. It will do 226 @ 2.5-3-2-5, though.

edit: I misread what type of RAM you have. That's BH-5 chips you have, if it's 2.5-3 years old. It will do 226 @ 2-2-2-5, if you give it ~2.85-2.9v vdimm. Oh, and only change the first four you listed. Just do it all at once. If it's some of the newer 2-3-2-5 RAM, then you'll need to go 2.5-3-2-5 @ 2.8v or less. Mine does 225 @2.5-2-3-5 @2.70v.

 

[wongnog]

Thanks, I am trying 226 @ 2-2-2-5 vdimm 2.80 right now. I believe this is TCCD based, I bought it in late Dec 2005. This thread from OCZ tells me not to go above vdimm 2.80, but I'll try 2.85-2.90 if it fails at the current timings, otherwise I'll loosen them a bit.
http://www.bleedinedge.com/forum/showpost.php?p=129911&postcount=2

 

[RichUK]

I was able to get mine all the way upto 289Mhz at 2.5-4-4-8 1T at 2.8 Vdimm fully memtest stable. I accomplished this on my opteron 165 ages ago. However other chips I have had like my Winchester 3500 and my current 148 do not perform the same, thus the on die mem controllers can be the limiting factor when trying to get the most out of your ram, especially high frequency TCCD ram.

Although you are using the opty 165 which is using the updated E6 mem controller, so you should be seeing much better results.

Try and lower the multi to 6, then up the HTT as far as it will go and run the memory 1:1. Just try and isolate the issue, TCCD are very good chips, and are easily able to reach around ~260Mhz at CAS 2.5. Also TCCD do not require crazy voltage like BH5.

 

[myocardia]

TCCD! Keep the vdimm at 2.80v, and put it at 2-3-3-5 timings in the BIOS. Then download this: A64 Tweaker, and change it to 2-3-2-5 from within Windows. If it handles it without rebooting, try running SP2004 or OCCT or whatever you use for stability testing, using Mixture, stressing RAM, too. If it passes an hour of that, you might possibly be able to get it to run at 2-2-2-5, but don't get your hopes up. Whoever told you that it was possible gives their's 2.9-3.0v vdimm, I can almost guarantee you.

 

[wongnog]

I think my ram is crap... I don't even get past the bios post screen at 226Mhz at anything tighter than 3-4-3-7. Right now I've lowered cpu multi to 6 and am trying HTT 250 with memory at 1:1. So far OCCT stable, I think it will pass dual Super Pi. Gonna see again how high I can get with these loose timings again. I'm still keeping vdimm at 2.80v. I was running SP2004 under custom testing and setting mem to 400, that seems to use 100% of each core. Would Mixture testing be better for mem only stressing? Appreciate any tips you guys can give.

 

[wongnog]

Okay, I decided to try vdimm 2.90V and even looser timings, and was able to hit 270 mhz (12 hr StressPrime 2004 stable). I tried 274 mhz but SP2004 gave errors after 2 hrs. I'm going to install an Arctic Cooling Freezer 64 Pro and a 120mm intake fan, and see if I get can htt beyond 277 mhz. Here are the timings I am trying now:

VDimm = 2.90 V
Cas latency (TCL) : 3
Min ras active time (TRAS) : 10
Ras to Cas delay (TRCD) : 4
Row precharge time (TRP) : 4
Row Cycle time (TRC) : 16
Row refresh cycle time (TRFC) :22
Read-to-write time (TRWT) : 6
Write recovery time (TWR) : 3
1T/2T memory timing : 2T

 

[wongnog]

Hey guys, thought I'd continue this thread. I installed that AC Freezer 64 Pro and am able to get my Toledo core Opteron 165 up to 293 fsb, 9h SP2004 stable. This was with the memory clocked down to DDR200. The memory I have is 1GB(2x512M) OCZ DDR Platinum Rev2 PC3200, which are BH-5 chips if I understand correctly. Obviously the ram won't run at 293 mhz, so I tried 240 mhz (DDR333) @ 3-4-4-10 2T (2.8v) but Stress Prime crashes after 2h. Here are the full timings I used:

Memclock index value: 333 mhz
Cas latency (TCL) : 3
Min ras active time (TRAS) : 10
Ras to Cas delay (TRCD) : 4
Row precharge time (TRP) : 4
Row Cycle time (TRC) : 16
Row refresh cycle time (TRFC) :22
Read-to-write time (TRWT) : 4
Write recovery time (TWR) : 4
1T/2T memory timing : 2
S/W Dram over 4gb remapping : Disabled
H/W Dram over 4gb remapping : Disabled

Hyper transport frequency : 3
Amd K8 Cool'nQuiet : Disabled

CPU frequency : 293
PCI Express : 100mhz
DDR voltage : 2.8
Chipset voltage : 1.6
HT voltage : 1.25
CPU multiplier : 9
CPU voltage : 1.50 (board's max on Toledo core Opteron 165)
PCI clock syncronization mode : 33.33mhz

Does anyone have suggestions on how I can get my ram to run @ 240? Right now I'm trying to underclock the memory to DDR266 (189MHz) @ 2-2-2-5 1T, so far it's 6 hrs SP2004 stable. Surprisingly I get a higher memory bandwidth score on SiSoft Sandra @ 189mhz 2-2-2-5 1T than 240mhz 3-4-4-10 2T. Weird huh?

I appreciate any help you guys can give