Checking memory voltages

[wraith3k]

Hi all,
I'm using 2x1GB Crucial Ballistix PC8500 on a Gigabyte P35-DS4 board. I've been having sporadic crashes and blue screens (like other people with this ram), and memtest shows a lot of errors.

The BIOS indicates it as running at 2.224v. Crucial says it should be 2.2. Is this too high, or is this a negligible difference? (This is in the field that says DDR18V). The system is not overclocked in any way.

Thanks

 

[JustaGeek]

I believe that 2.2V is the maximum. Try running it at the lowest stable voltage.

My 4GB kit calls for 2.2V, and I am running it at 2.0V, although at 667MHz.

Try running yours 1:1 with the FSB and at a lower voltage.

Good luck!

 

[wraith3k]

Unfortunately I'm a noob at this stuff so even though I know 1:1 means so the FSB and DRAM speeds are equal, I don't know how to change that. Also, I didn't see any way in the BIOS to actually lower the voltage, just raise it. I changed my timings to 5-5-5-15 though (they were 5-5-5-18 before), so now it matches what Crucial says it should be.

Here is what cpuz shows, if it helps:

Memory
SPD

In the second picture, notice that the timing table shows 5-5-5-18 is @ 1.8v. The spec for my ram is 5-5-5-15 at 2.2v. So I don't know why the BIOS would automatically set it to 5-5-5-18 @ 2.2v, unless it was using the wrong info somehow. I also don't know why it says PC2-6400 at the top, since I have 8500.

 

[JustaGeek]

I am not familiar with your MB, but your memory is now running at 1066MHz, with the Front Side Bus at 266MHz, correct...?

Not all the motherboards will successfully run the RAM at these frequencies.

Try to change the RAM frequency to 800MHz, by adjusting the RAM/FSB ratio to 3:2 (it is now at 2:1 - or as it shows in CPU-Z 1:2).

Try that and we'll see if that helps. And lower the memory voltage to 2.1V (time to open the MB manual )

BTW, the SPD might say PC2-6400, but the memory was tested at PC2-8500 speeds.

Which (again) doesn't guarantee that every motherboard will be able to run it at these speeds...

 

[rezilient1]

Hey man, I found your thread.

Since you are running your RAM at 1066mhz I would suggest trying 800mhz. What motherboard are you using, I'm sure someone will be able to help you find it.

Edit: Okay I missed where you mentioned your motherboard, just saw that.

 

[wraith3k]

Correct, the memory is at 1066 and FSB is 266.

I've checked the manual for the board, but see no mention of how to lower the voltage. It just lets you increase it in .05v increments, and it is already set to the default of 'normal'.

How do I lower it to 200 so the memory runs at 800 instead? And, maybe this is a dumb question, but would lowering the FSB speed in turn also end up lowering the cpu speed, or can that be avoided?

 

[JustaGeek]

Are you sure you're running it at 2.2V...?

Perhaps someone with the same MB will help you, but i believe that you are now at 1.8V. Try to increase it by 0.3V, to get to 2.1V, and change the ratio to 3:2, or 1.5. (however it is shown in your BIOS).

But read the manual first! If you are running it at 2.2V now, increasing the voltage will damage the dimms!

 

[wraith3k]

The BIOS indicates that it is 2.224v, which is what the DDR18V line on the PC Health screen says.

 

[LOUISSSSS]

set your voltage on your RAM to +0.4 (or +0.35) and also raise your northbridge (MCH), and FSB voltages up +0.1v

 

[JustaGeek]

Page 52 of your MB manual explains it:

System Memory Multiplier
Allows you to set the system memory multiplier. Options are dependent on CPU FSB. Auto sets memory multiplier according to memory SPD data. (Default: Auto)

Memory Frequency (Mhz)
The first memory frequency value is the normal operating frequency of the memory being used;
the second is the memory frequency that is automatically adjusted according to the CPU Host Frequency (Mhz) and System Memory Multiplier settings.

High Speed DRAM DLL Settings
Provides two different memory timing configurations. If your system becomes unstable after you overclock the DDR2 memory, select Option 1 or Option 2 to help make your system more stable.
Option 1 Memory Timing Configuration 1. (Default)
Option 2 Memory Timing Configuration 2.

DDR2 OverVoltage Control
Allows you to to set memory voltage.
Normal Supplies the memory voltage as required. (Default)
+0.05V ~ +1.55V Increases memory voltage by 0.05V to 1.55V at 0.05V increment.
Note: Increasing memory voltage may result in damage to the memory.

I guess Luisssss can take it from here on...

Good luck!

 

[wraith3k]

Thanks JustaGeek, but given that the voltage already reads 2.224v, I don't know if I'd want to do another 0.4v. From what I've been reading the people that are adding another 0.4 are the ones who have it currently at the default of 1.8, thereby bringing it up to 2.2. As far as lowering the FSB speed, well I guess I'll play around with those settings to see what happens.

Edit: Everest also reports the DIMM voltage as 2.22v.

 

[JustaGeek]

I believe it is running at 2.22V because it is set to NORMAL.

If you set it manually, it will do it as the base 1.8V plus whatever you add, ex. 0.3V will result in memory running at 2.1V.

Add 0.1V, and check the reading in BIOS (after Save and Exit). If it reads 2.32V, it is too much, so change it back to 2.22V. It shouldn't fail if you change it right back.

But... if it reads 1.9V, you know that you can safely add 0.3V for the final 2.1V.

And change that ratio to get it running at 800MHz. Pick 1.5 ratio, it will give you RAM speed of 800MHz.

 

[rezilient1]

Originally posted by: JustaGeek
I believe it is running at 2.22V because it is set to NORMAL.

If you set it manually, it will do it as the base 1.8V plus whatever you add, ex. 0.3V will result in memory running at 2.1V.

Add 0.1V, and check the reading in BIOS (after Save and Exit). If it reads 2.32V, it is too much, so change it back to 2.22V. It shouldn't fail if you change it right back.

But... if it reads 1.9V, you know that you can safely add 0.3V for the final 2.1V.

And change that ratio to get it running at 800MHz. Pick 1.5 ratio, it will give you RAM speed of 800MHz.

JustaGeek is right, I had a Gigabyte EP35-DS3R and thats exactly how it worked. Auto settings would make it "around" 2.18V and setting it manually allows you to pin it down with more control, taking 1.8V as the base and +whatever.

 

[wraith3k]

That makes sense, but this is what happens. If I set it to Auto, it reports it as 2.224v. If I change it back to Manual, with everything else below that set to Normal, it again is still 2.224v. At no point have I ever seen it at 1.8v. I've read other threads and it seems the DS3 series do have a base of 1.8v, the reason why many others add that extra 0.4v. Could Gigabyte have changed it for the DS4 series (what I have)?

As far as speed goes, I'll mess around with the settings to bring it down to 800mhz. If I understand right, I think I just need to change the System Memory Multiplier to 3 (therefore giving me 266x3=800).

 

[JustaGeek]

I don't know your motherboard, so it is very hard to give you detailed instructions.

The multipliers work as follows:

The CPU has a multiplier of 4 (quad-pumped) and everything revolves around the "base" Front Side Bus (FSB) frequency.

Yours is 266.6MHz.

266MHz x 4 = 1066MHz CPU frequency.

266MHz x 1.5 "memory divider = 400MHz Memory Bus x 2 (Double Data Rate - DDR) = 800MHz.

Presently you are running 266MHz x 2 memory divider = 533MHz memory bus x 2 DDR = 1066MHz.

Too fast... slow it down with the 1.5 memory divider (some call it "memory multiplier", but that only confuses the issue more).

 

[LOUISSSSS]

did u get ur ram working? if not, did u bump your MCH and your FSB voltages up +0.1v?

 

[wraith3k]

Well, it's working at the moment, but that's what has been happening - works fine for a few days, then dies. I'm going to tweak it a little at a time to narrow down what the problem might be. I haven't yet bumped up those voltages though. Appreciate the input, I'll post back here with results.

 

[LOUISSSSS]

what do u mean by "dies." when tech people say 'dies' it usually means that it doesn't work after that...
so you're saying your pc works fine, then freezes randomly until u restart it?

 

[wraith3k]

Let's say I power on the computer and leave it on...it'll be fine for a few days, then I'll start getting sporadic program crashes and blue screens, and memtest will throw errors everywhere. I'll turn it off, power it back on several hours later, and it's fine again. Then a few days go by and the same thing happens. Power it off again for a while, back on a few hours later, works again. Thinking that maybe it's also a heat issue, I'm running with another fan blowing over the memory now.

 

[wraith3k]

Update - started getting sporadic program crashes again this morning. Ran memtest for about 10 seconds and immediately got errors. Booted into BIOS and changed my system memory multiplier (which apparently is the same as the divider mentioned earlier) to 2.5, the first possible option. *Now* my memory voltage read as 1.8v, so I overvolted it up to 2.192v, the closest I could get it without going over 2.2v. Ran memtest again for a minute without any problem. My memory is only running at 333mhz dual channel now, but I'll see if it remains stable like this before increasing it again.