Need Help with Buying Memory for Old System (DDR3 / P55)

Hi Folks;

I could use some help with buying some memory for an old system that I still use all the time. It uses DDR3 memory and has the Intel P55 express chipset with a Xeon X3470 processor.

The issue is that I would like to be free to overclock this system. The processor OC's very well but the existing memory....not so much. It also needs more memory so...
Back when I bought the original memory I bought the wrong stuff, I think it was rated at 1300 and I should have bought at least 1600. I bought the 1300 based on bad advice given at the time. I've regretted it ever since.

So this time around I would prefer to buy memory from the extreme other side of the equation. Ie, memory that's so fast I probably will never be able to go that fast (if that makes sense - what I'm trying to do is remove memory ability from the equation) and more importantly, not regret what I buy!

The mainboard is an Asus P7P55D-E LX and it uses DDR3 Dimms apparently up to 2200 (OC) Dual Channel. It has the latest/last BIOS in it.

I was looking at these ones;

http://www.newegg.com/Product/Product.aspx?Item=N82E16820231589&cm_re=ddr3-_-20-231-589-_-Product

which are 2400. But, I read some articles on them and they are apparently designed for a newer chipset, the Z77.
Does that mean they would not work?
Can I buy memory that's rated to 2400 and run it at lower speeds at will?

The last time I was fluent in memory it was PC133

Look here for the official list:
http://www.asus.com/US/supportonly/P7P55D-E LX/HelpDesk_QVL

http://dlcdnet.asus.com/pub/ASUS/mb...y_QVL.zip?_ga=1.31194616.655320388.1473190147

The second link is the PDF in zip form of the qualified vendor list. It is six pages long and is sorted by memory speed.

If the RAM is DDR3 and *not* DDR3L and runs at the 1.65 - 2.0 volts, your MB should not have a problem supporting it. Remember that your board does not support more than 4 GB per slot as listed here:
https://www.asus.com/Motherboards/P7P55DE_LX/specifications/

The kit that you linked to will not work because it is too large. 16 GB total for your board divided by the 4 slots available = 4 x 4 GB = 16 GB.

It's the details that will get ya.

What are the limitations of the motherboard on memory speed?

don256us said:

Look here for the official list:
http://www.asus.com/US/supportonly/P7P55D-E LX/HelpDesk_QVL

http://dlcdnet.asus.com/pub/ASUS/mb...y_QVL.zip?_ga=1.31194616.655320388.1473190147

The second link is the PDF in zip form of the qualified vendor list. It is six pages long and is sorted by memory speed.

If the RAM is DDR3 and *not* DDR3L and runs at the 1.65 - 2.0 volts, your MB should not have a problem supporting it. Remember that your board does not support more than 4 GB per slot as listed here:
https://www.asus.com/Motherboards/P7P55DE_LX/specifications/

The kit that you linked to will not work because it is too large. 16 GB total for your board divided by the 4 slots available = 4 x 4 GB = 16 GB.

It's the details that will get ya.

Click to expand...

Thanks - I appreciate the help!!

With this motherboard and processor combo it's always been a little bit challenging with respect to memory support. I bought the board new years ago when their was only 1 or 2 BIOS releases for it (it was still pretty new). Since then there's been maybe 10 and it EOL'd some years back.

What I did notice was that the qualified memory list from Asus was never updated so I didn't put much stock in it. I currently have 4 slots of 2GB and it's been like that for years.

A year back or so I got the Xeon x3470 processor. It overclocks like you would not believe but my memory has held me back. I also need more then 8GB due to memory sucking applications...

Anyway, here's where it gets interesting. The ASUS memory list only seems to show 4GB sticks as the maximum.....but...the X3470 processor supports 32GB total. The memory controller is on the processor. To get 32GB you'd have to have 4x8GB in the system. In other words, the limitation appears to be (to me) the processor and not the board.

I could be totally wrong with my conclusion but I'm really hoping that 8GB sticks should work...

- - - Updated - - -

trents said:

What are the limitations of the motherboard on memory speed?

Click to expand...

I don't think there are any. I looked at the BIOS last night and this is what I saw...

The DRAM frequency appears to change if I increase the BCLK frequency.
The stock BLCK is 130 which makes the options for DRAM 780, 1040, 1300, 1560.
If I increase the BLCK to 131 (go up by one) the DRAM frequency choices change to 786, 1048, 1310, 1572
I can adjust the BLCK from 80 all the way up to 500 – at 500 the CPU would be doing 11,000 Mhz and the Memory options are 3000, 4000, 5000, 6000 

DRAM voltage can go from 1.2v to 2.0v

I don't know a lot about overclocking but, as I recall, when I bought the board I wanted one that would overlock very well. That was probably 6 or 7 years ago.... It was only last year I got the processor and I found out the people used to regularly run them all day long at 4.5 Ghz. So I said to myself I'd OC it later when I do something with the memory. It's looking like that time is coming.

Hopefully the stuff I saw last night indicates that it's granular with respect to overclocking.

You have to ask yourself first of all if you would use 32GB of memory most software won't.
I would look at a decent kit of 4x4 GB 1600. You won't be able to run at 2400 and no sense in paying the premium for the sticks.

Maybe not able to run at 2400 but the list shows support for memory up to 2133 (which is a speed I've not seen before).

The 4 GB/8GB is a good question that I do not know the answer for. To be safe, we know that it will support 16 GB.

Here's a 4x4GB set on sale until Friday for $75. 1600 CAS 9 is plenty of speed for overclocking too.
http://www.newegg.com/Product/Product.aspx?Item=N82E16820231545

This is awesome - glad to see people interested in this 'old' system and actively helping.

I spent a lot of time researching this over the last two days using keywords x3470 and memory support etc. I found very little as the processor was not used much because most people did not understand that it was actually the same as an i7-860 but better.

OTOH, I realized today that a lot of people did use the i7-860 and changed my search terms looking for installed amounts of memory. Turns out, I saw several similar posts and people were able to ue 2x8GB sticks with the i7-860 and one fellow, with a nearly identical board, got 4x8 (32GB!!) working with an i7-860 - even though that processor does NOT support that.

My conclusion is that it's safe to ditch my 4x2GB sticks for 2x8GB and will have room to add in two more since the Xeon x3470 does support 32GB. Thread on fellow that did it (same chipset/pretty much same board).

The interesting thing is he posted this on December 6th (today!!!!!!).

http://www.c-amie.co.uk/technical/p7p55d-ev0-32gb-ram/

Price is important but....if I can go 2x8 and leave two empty slots for the future...at an added cost of about $30 with the ability to go to 2400...I'm thinking that would be smarter.

I don't know how much the speed of the memory should be weighed into the equation. The stuff I was looking at is this;
http://www.newegg.com/Product/Produ...7702X1552850X7e5151af5029ea14bdcb35430d1a8e07

and it's 10-12-12-31
My existing memory is 7-7-7-x

You have never once said what you're going to be using this system for and as I said earlier 16GB is plenty. UNLESS you're working in AUTOCAD or doing some very heavy video rendering you're never going to use 32GB of memory. That kit that JLK0 linked is a good price and if it's speed you're worried about not many applications will be overly affected by ram speed. the kit linked will likely run at 1866-2000 fairly easily with modest volts and loosened timings.
You seem bound and bet to get 2400 memory when that is likely just going to make your OC harder. Another thing about xeons is typically they run slower memory since it is a server part and accuracy is the goal not high performance so slow speed ram is typically what they run. In the end it's up to you what you buy which may or may not work. But I'm certain that 4x4 kit linked will work just fine. Plug and play.

It's primarily used for commercial scanning so it's very CPU intensive.

Got my water cooler installed. Went from 2.93 to 4.209 totally stable with a mild overclock of the 1333 to 1530. Found out along the way that the multiplier was cutting in half (throttling) for some reason. The heat sinks around the CPU were too hot too touch so I added in another fan that blows directly on them and throttling was reduced a lot. Very noticeable.

I'm still seeing throttling when stress testing the CPU though. It seems I haven't cased it completely. Processor temps never rise above 83 so I know it's not a temperature issue on the proc. Given that cooling the heat sinks around the proc made such a difference I'm leaning towards it being cooling or something on the mainboard itself.

The system has 16 TB in video storage and it's using the majority of the 8GB in memory. I think the smart move will be to buy the two sticks I referenced above which will give me room to grow while at the same time expanding the available memory and removing memory speed from the equation. Next step up in memory speed in the BIOS seems to be something around 1800 and I don't think I can get that with these 1333 sticks.

Wish I knew what was causing the multiplier throttling during testing though. All the power saving features have been turned off.

I am guessing that you are throttling on temperature. I think the max CPU temp you want is going to be 75C-80C. You also need to make sure the case is well ventilated to get the heat from the power section out of the case. Adding a fan there is spot on! Much needed when overclocking & water cooling.

Speaking of adding fans, you'll need another fan mounted to your RAM if you decide on a kit rated at 1.65v. I like to stick with RAM rated for stock volts (1.5v) if the rig is not strictly for running benchmarks. If you really want to try 2x8GB...
Newegg has another deal, this weekend, G.Skill 1866 CAS 9 2x8GB kit for $79 shipped.
http://www.newegg.com/Product/Product.aspx?Item=N82E16820231615
They also have G.Skill 2133 CAS 10 2x8GB for the same price, BUT it is rated for 1.6v at that speed.
http://www.newegg.com/Product/Product.aspx?Item=N82E16820231660

Just out of curiosity what are you running your CPU and RAM at voltage wise?

JLK03F150 said:

I am guessing that you are throttling on temperature. I think the max CPU temp you want is going to be 75C-80C. You also need to make sure the case is well ventilated to get the heat from the power section out of the case. Adding a fan there is spot on! Much needed when overclocking & water cooling.

Click to expand...

I agree that it must be temperature related. What I'm seeing when running Intel Burn Test is that, depending on how much voltage I send through the CPU, the first few rows are fast with no multiplier throttling. After a few rows, it begins to drop the multiplier for a time and then raise it back up. Watching the CPU temps during the process shows that it's hovering around the high 70's.

There does not seem to be any real correlation between the CPU temperatures and the multiplier cut. I've been watching this carefully, and historically the CPU has run right up to 100c on the old air cooler. I believe that's when the CPU itself cuts the multiplier. Average temps with that cooler were way, way up there. In fact, the goop between the OE Intel air cooler and the CPU was burnt brown in color and had bubbles on it and stank. SO it had been running hot for a long time before I noticed it (more then a year).

With the water cooler the max temperature shown in 84c and this is just a flier. Normally it's in the high 70's when under full load and clocked at 4.2 The TDP of the processor is 95 watts. The max voltage from Intel is 1.4v (I'm at 1.408).

When I concluded something else must be dropping the multiplier I checked the heat sinks around the CPU. They were all too hot to touch. After installing the fan they were now able to be touched and you could hold your finger on them no problem. This made a dramatic difference in decreasing the throttling. It's now throttling again but I am at a much higher clock (the 4.2).

This lead be to believe it must be mainboard related. I think I'll pop the board out and remove the heat sinks in those areas and clean/apply new goop and see if that helps.

The idea of using lower voltage RAM sounds smart and I had not thought to consider it. I'm guessing the less voltage a fellow has to put through anything on the board the less heat becomes an issue and the better chance you have of OC?

Here's some pics of the old girl. The case has a separate power supply 'chamber' with the idea being that the PS heat is separated from the rest of the case. I put arrows on one of the pics showing air flow in the top half. The fan at the front middle of the computer is not working because I have no headers left for it on the mainboard. When I put the top fan in I mad to make a choice but there is a LOT of air going over the CPU and the memory from the top fan. All air is reverse flow (intake at rear, exhaust out the front).

Theocnoob said:

Just out of curiosity what are you running your CPU and RAM at voltage wise?

Click to expand...

CPU voltage set in the BIOS is 1.4125 (Intel says 1.4 is max limit)
IMC is set to 1.4v
Memory voltage is set to 1.66v
RAM is 1333 7-7-7-21 set to 1528 7-7-7-21
BCLK is 191
Max CPU temp under full load is 83c

I checked and Intel lists the thermal threshold of that chip at 72.7 degrees(i don't know why such an odd number) so you are probably seeing throttling due to your temperatures. The AIO you have is a little undersized for this chip especially when overclocked. I would either invest in a better cooler or lower your overclock a little. You may actually see better performance by backing off the overclock as you will avoid throttling.

Lochekey said:

I checked and Intel lists the thermal threshold of that chip at 72.7 degrees(i don't know why such an odd number) so you are probably seeing throttling due to your temperatures. The AIO you have is a little undersized for this chip especially when overclocked. I would either invest in a better cooler or lower your overclock a little. You may actually see better performance by backing off the overclock as you will avoid throttling.

Click to expand...

This turned out to be some pretty remarkable advice....but first.....

The stinkin' thing kept cutting the multiplier in half, even when I felt it shouldn't. After looking through the BIOS I found this setting;

CPU TM Function: Enabled <= Enables the overheated CPU to throttle its clock speed to cool down.

This was a remarkable discovery. Keep in mind, at that time, at the clock settings I was using, it was hitting 80 on the top end. So I disabled that setting. Guess what? The multiplier stopped getting cut in half So then I was a little worried, does this mean I can melt my chip? As it turns out, no. It stops the multiplier from cutting in half but when the chip determines it's too hot, the computer shuts off instantly

So this was good to know as it gave me a very real and accurate way to determine at what temp the CPU felt it was too hot. I had been thinking 90....you said you found the spec to be 72.7 - I was initially skeptical about that. But here's what happened in the real world....

After a lot of testing and fine-dialing what I found was that 74c was OK. If any core hit 75 it was a crap shoot. If any core hit 76, you were doomed. Even if it just flashed up to 76 for the briefest of moments, you were doomed. So I beat your 72.7......but not by much which tells me that it's an accurate figure. And you were right on the beam as well with a larger cooler. There is room to go on this chip, probably a fair bit, but I'm now constrained by the 74c threshold.

As to your last point, here's what I was seeing when the multiplier safety was in effect. Burn test results would start at 18 seconds and then grow until they hit 27 seconds as the CPU was cutting the multiplier when I was at +/- 4.2Ghz So I cut the BLCK back to 4.012 Ghz and was able to get;



So 4.012 is much faster then 4.2 Ghz because it's a solid 4.012 all the way though (no throttling). 4.2 Ghz is not really 4.2 Ghz because it's only 4.2 Ghz for maybe 50% of the time....It's only good to impress your friends.

The CPU settings for the 4.012 were as follows;

Intel LGA 1156 / P55 Express Chipset /Xeon x3470 2.93 Ghz Processor @ 4.012
BCLK = 182
CPU V = 1.30625 (precisely, and absolutely critical any more and the temps too high, any less and sporadic fails)
IMC V = 1.30

This left the memory which was G.SKILL 1333 7-7-7-21 @ 1.5v which became;
1820 @ 1.6v @ 9-8-8-24

I might be able to get more out of the memory but as mentioned, it's due to be replaced anyway as I need more then 8GB and possibly as much as 32GB at some point.

This made a really big difference in the speed of the system. It was very much an in-place upgrade. Once I install 3 SSD's in it the system will be more/less instant again.

Any thoughts on the findings above are appreciated (ie, if they look right) but I was really surprised how accurate your post turned out to be. I'm currently running a new (as of yesterday) H60 cooler. I don't know what could be better and still fit in the case - 120mm ?

Many thanks to everyone. It's good, in fact, it's great! It took quite a bit of time but I am certain given the current temperature constraints on the CPU - this is as good as it gets.
BTW, a quick look on the Internet seems to indicate the world record for this proc on water is only 4.2 Ghz @ 1.44v (!!) This really makes me think I could eat that for breakfast. I had it in Windows at 4.5 Ghz when it had the auto-throttle engaged and it was solid, albeit, getting throttled.

BTW, it seems to me there's also a quality issue on the overclock. At some point I started looking at the output times from Burn Test and trying to adjust for very consistent numbers. In fact, it seemed like I could sense, from the number spread, when I was not going in the right direction.

don256us said:

Maybe not able to run at 2400 but the list shows support for memory up to 2133 (which is a speed I've not seen before).

The 4 GB/8GB is a good question that I do not know the answer for. To be safe, we know that it will support 16 GB.

Click to expand...

I've got a dual channel kit of DDR3 2133 running in a board right now. It is certainly available.

trents said:

I've got a dual channel kit of DDR3 2133 running in a board right now. It is certainly available.

Click to expand...

It's my understanding I can actually run faster memory then the system supports - just at a lower rate. I'm going to check the BIOS and see what the next step is after 1820. Perhaps it will be something I can run - that would be too cool!

Tj Max is a 100c then it will throttle, check with RealTemp.

I'm not sure about the effectiveness of your air flow. I would have to look into it again but I recall that testing has shown that it is better to exhaust hot air out than to pull cool air in. The way I see it is that you are forcing warmer air into the center of the case and trying to force it out. The difference is positive air flow vs negative air flow. Negative air flow is generally better at pulling hot air out while bringing in more cool air surrounding the case.

I'd be willing to put money on it that if your pushed air out from the top and the back that your temps would drop. In other words, reverse the two arrows at the top of your picture.