twin2x2048 8500c5d timings

[jimmsch]

I bought this high speed RAM hoping I will be able to run it at 400-420Mhz with tighter timings on a P5B Dlx WiFi. Well even with 1.65 NBvcore and 2.4vdimm I get errors on Memtest86 starting on test 3 and just erroring across the board on every test after that as soon as I tighten just ONE of the first 3 timings to 4 clocks. Doesn't matter which one. It passes at 402Mhz with 5-5-5-15, but I cannot say for sure if it will do the rated specs or not as I don't think my e6600 on that rig will get me to 533fsb.

Is there some setting I missed in BIOS?

[jimmsch]

Hmmmm Each stick passes memtest individually in all four slots on mobo at rated specs of DDR21066 5-5-5-15. When I put both sticks in together in slots 1 & 3 I get errors. Using slots 2 & 4 also generates errors.

I put two sticks of XMS2 DDR2800 in the same board and passes memtest so far in slots 1 & 3, will try slots 2 & 4 in a few minutes.

It looks to me like these Dominators are not working together in dual channel.

[Yellowbeard]

It looks to me like these Dominators are not working together in dual channel.

Dual channel is solely a function of the MOBO. If they are passing Memtest, the problem is not likely the memory.

[jimmsch]

Thanks for that reply Yellowbeard. The mobo dual channel works as the XMS2 DDR2800 passes memtest and is verified dual channel in both the POST as well as CPU-Z.

These Dominators will only pass memtest individually, installed in the same rig as the XMS2 modules. When I put them both in and set the settings to factory specs they fail memtest. They even fail memtest at DDR2800 speed and factory spec timings of 5-5-5-15, still with 2.2vdimm. No matter what I do they fail memtest when both are installed.

I ruled out the mobo by getting the XMS2 DDR2800 sticks to pass memtest working together in dual channel. Like I said I even tried the Doms at DDR2800 speeds and failed. The XMS2 sticks have passed all the way up to DDR2900 speeds.

There is a problem with this RAM and I just got it two days ago, never even tried to boot windows with it yet because I want to make sure it passes memtest first, which it does not.

[Yellowbeard]

Keep in mind that on most 975x chipset boards, you are not going to be able to run memory at 1066mhz. Most of them top out at about 1000mhz MAX. So, if you are failing at 1066mhz but the memory tests OK at 800, then most likely you are topping out your MOBO. It's the chipset, not the memory.

I'd suggest you manually clock upwards from 900mhz and find your max OC.

[jimmsch]

Thanks Yellowbeard, but you didn't read my post thoroughly.


I bought this high speed RAM hoping I will be able to run it at 400-420Mhz with tighter timings on a P5B Dlx WiFi.

This board uses the 965 chipset.


Like I said I even tried the Doms at DDR2800 speeds and failed.


They DO NOT pass Memtest86 when both sticks are in the board. I tried at factory rated specs (1066...5-5-5-15-5...2.2vdimm) Resulted in multiple errors from test three and the rest of the way through Memtest86.

I tried them at lower specs (800...5-5-5-15-5...2.2vdimm) Same failures on Memtest86.

The funny thing is the XMS2 sticks pass Memtest86 all the way up to 900 speeds with 5-5-5-12-5 and only 2.15vdimm.

All of this testing is being done in the same system.
What more should I try?

Thanks -Jim

[jimmsch]

OK Yellowbeard, it might not be the RAM. I tried memtest86 with same exact settings I used for the XMS2 sticks. The only difference was the vdimm.

The RAM passes at DDR2-820 speeds 5-5-5-15-5-42 using 2.10vdimm. At same settings using 2.2vdimmm they fail. At their rated specs and 2.2vdimm they fail. I will try 1066 5-5-5-15-5-42 at 2.10vdimm and see what happens.

What do you think is causing the failure at 2.2vdimm?

P5B Dlx WiFi AP/Solo (1101 BIOS)
e6600 (410*7 1.38vcore)
74GB Raptor
Samsung IDE DVD burner
TT Big Water (cpu only) 120mm fan on rad
One extra 120mm intake fan blowing directly on the RAM
ATI X600 (powered by PCI-E lane only...no fan..no 6pin power)
Obviously, the Dominators (1:1 with CPU 5-5-5-15-5-42-10-10-10-11
Ultra V Series 400watt PSU

It is a pretty basic system, but my guess is the PSU.
Let me know what your guess is.

Thanks -Jim

[jimmsch]

YUP It was the PSU. I switched it out for an Ultra XVS series 700watt PSU and it passes Memtest86 at factory recommended specs. I hope this doesn't mean it wil need the 8 pin ATX power since I ultimately want to use this on my P5W DH Dlx which only has the 4 pin.

My apologies to Yellowbeard for my insistance that this was a RAM problem. I was wrong.

Now to see if I can get my tight timings (hopefully 3-3-3-8-3-30) at DDR2 820 speeds. Wish me luck! Obviously if I am not able to get these timings I will have no complaints...the RAM runs as it is supposed to.

Thanks -Jim

[Yellowbeard]

Good luck with tuning the timings.

[jimmsch]

Yellowbeard, do you know what IC's these sticks have? They are v1.2 acquired from ZZF on May 21, 2007.

They are giving me fits again. Couldn't get stable Memtest86 at DDR2 820 4-4-4-12-4-42-10-10-10-11 4-4-4-15 didn't help. All the way up to 2.4vdimm didn't help.

I went back to 5-5-5-15-5-42 and error again at DDR2 820 2.25vdimm. So I went back to factory specs that worked earlier, and error again. Same exact settings that worked a few hours ago are erroring. Any ideas?

[buffbiff21]

The 8500 Dominators and up should still use Micron D9.

Are you making sure you're using 1:1 FSB:RAM? Like Yellowbeard said it could be the chipsets limitations... I think it places strain on the memory controller (northbridge) to run highery RAM speed than the FSB, especially when overclocking the CPU. (I'm currently doing research on this myself :) as I'm having trouble with these sticks on my DFI Infinity P965 board)

[jimmsch]

Unfortunately I can't run 1:1 and test 1066 speeds. I have to run a 1:2 divider with CPU at default 266, which it passed memtest86 once. Other than that I always run 1:1 at 410 on the CPU and DDR2 820 speeds on the RAM trying to get timings a bit tighter.

After trying to tighten the timings and failing I went back to the 1:2 divider and failed memtest86 at the same settings that passed earlier. WEIRD

[buffbiff21]

Unfortunately I can't run 1:1 and test 1066 speeds.

Why not? Can't your P5W get up to 533 FSB? Drop your CPU's multi. I've seen it done.. my old P5W got up to 500 stable. Increase vMCH maybe.

[dinos22]

high FSB has a LOT to do with the CPU buddy

[jimmsch]

For the time being I am running these sticks on a P5B Dlx with r6600. I can't get it to boot much higher than 490.

I have never heard of a P5W DH Dlx doing much more than 450.