DDR3 1800MHz supported?

[galacticman]

I was determined to upgrade my AMd 64 1Gb machine and I did just this but...
I bought Gigabyte GA-MA785GMT-UD2H AMD785G mATX AM3. I really wanted a Gigabyte board for my new build. I planned to use 1800Mhz DDR3 as various websites claim this board can run with 1800MHz + DDR3! Great. So I steered clear of the slower DDR3 1600MHz and decided to step up a notch to 1800MHz.

I got some Zeppellin 2x2GB 1800MHz CL8 DDR3. The board defaults to slowest DDR3 1066MHz (x4 multiplier). The x8 multiplier is needed for 1600MHz DDR3. This is frustrating as I have 1800MHz DDR3 Cl8 running at 1600MHz as this the maximum permitted in the BIOS. So how on Earth can the board run 1800MHz DDR3?


I don't know how to get the DDR3 running at the 1800MHz it's capable of. I think I need Easytune6 to overclock but this program won't run.


Any help?

System: Amd 965 Phenom II x4 3.4Ghz Black edition

Gigabyte GA-MA785GMT-UD2H AMD785G mATX AM3

2x2gb PC14400 1800MHz DDR3 Zeppelin

1Tb Samsung F2 ECO green.

Samsung SH223 22x DVD Rewriter.

Case: Shiny Red & Black with lcd display

All from ebuyer except for the DDR3.

Best Wishes

Paul

 

[bilbat]

You will need to raise the Bclk (CPU Frequency in the BIOS) to 237...

 

[galacticman]

the Bclk? CPU runs at 3.4Ghz which is spot on. Are you saying i need to increase CPU frequency to increase Ram speed to 1800MHz. This is my first real build and it's frustrating that the 1800MHz + isn't more easily acheivable.

Should i mess with memory timings? Also will it matter that DDr3 voltage is 1.7V instead of 1.8V?

 

[bilbat]

You can't 'dial in' any memory multiplier you want; though they are expressed as a decimal number - they are not! They are integer ratios, denoting bus frequency dividers/multipliers: 4.00 is 2:1; 5.33 is 8:3; 6.66 is 10:3; 8.00 is 4:1... These are set, in hardware, by configurable 'strap' bits in the processor - what you gets is, well, what you gets! Again, to hit an oddball frequency you need an oddball clocking, as the mult's are fixed.

 

[galacticman]

Thank you. So to accomodate the 1800MHz DDR3 I need to increase the FSB frequency?

What does Bclk stand for, FSB clock?

Am I right in thinking Ii's v difficult to get DDR3 running at exactly 1800MHz?

 

[JDFan]

Thank you. So to accomodate the 1800MHz DDR3 I need to increase the FSB frequency?

What does Bclk stand for, FSB clock?

Am I right in thinking Ii's v difficult to get DDR3 running at exactly 1800MHz?

Correct - Bclk == Base Clock (aka FSB) and a Bclk of 225 with the Ram Multiplier set at 8 will give you 1800 (225x8 = 1800)!!

 

[bilbat]

Gaakk! Dunno how I flubbed the math the first time, but, praise Murphy, I'm FINALLY (thirty-one days for a 'cross-ship'!) back on my normal ( exceedingly fast, four-monitor) workstation, so this can get back to normal (at least, after I hit the 'driver of the week' clubs at ATI, and RealTek )

Everything has a Bclk, but it's not always actually called that in their documentation; for the new Intels (i5/i7) it's 133 MHz; for AMDs, it's 200MHz; for Intel 775s, it's the FSB / 4...

 

[galacticman]

thanks again, the 227 seemed strange but I went into bios and looked. CPU Host controller frequency is 200, so as an experiment I altered to 201 and DDR3 frequency increased to 1608MHz. So, I need to increase to 225 to get to 1800MHz. But the AM3 965 frequency will increase and the northbridge,fsb etc.

Will the board be able to able to withstand such a big change or am i worrying to much? This set up cost a bit so i'm very cautious and never overclocked before and wish i didn't have to.

I wish I'd have just bought 1600MHz DDR3. 3.5Gb of the 4Gb DDR3 1800MHz is usable.

CPU Z says Ram is PC12800 but i wonder if it's basing this on 1600MHz frequency.

 

[bilbat]

Your processor may do the necessary 3.8 with no (or maybe a tenth) voltage increase; or, if you really don't want it OC'd at all, you can lower the CPU multipler from the stock 17 to 15: 225 x 15 = 3.375, just a tiny tad lower than the rated 3.4...

 

[JDFan]

I also have DDR3 1800 RAM that I just run at 1600 with lower voltage (they are rated 1800 8-8-8-24-2T @1.9V and I run them at 1600 8-8-8-24-1T @ 1.7V ) I mainly bought the 1800 rated kit since it was a few dollars cheaper than comparable 1600 modules when I purchased and it does give me the overhead if I do decide to increase the Bclk when OCing - so if you really do not want to OC then you can run them at the 1600 speed and they will run fine and then if you do decide to OC the system later at least you have the RAM that should allow it !

 

[galacticman]

ahh, how do i alter the stock multiplier. there's a CPU ratio which is an auto and manual settings start at 5 upwards. Could you give a bit more detail on how to do this please?

you say the cpu would cope at 3.8 but how about the FSB?

 

[bilbat]

There is no front system bus on socket AM2, AM2+, or AM3 systems...

To lower the multiplier, go to the "MB Intelligent Tweaker(M.I.T.)" page of the BIOS and change "CPU Clock Ratio" from 17.0 to 15.0; also, set "PCIE Clock(MHz)" to 100 (not 'auto', as for some boards, the auto setting doesn't work correctly at a higher Bclk...

 

[galacticman]

JDFan: Great to know u also have 1800MHz DDR3 running at 1600MHz. I set voltage at 1.7V also but am experimenting with 1.65V.

CL8 I believe. Oh when i first installed RAM default was 1066MHz and on bootup just 2.75Gb usable but at 1600MHz 3.5Gb usable.

Nice to know the 1800MHz will be fine running at 1600MHz, I did worry about voltages being slightly out or timings.

I'll try to post timings.

easytune6 won't run either and I believe that would find the optimum settings.
It's good to know there are options.

bilbat: Thank you again. I'll consider both overclock and underclock options. Seems like a trade slightly slower CPU clock for 1800MHz DDR3 running to full potential.

 

[JDFan]

Yeah the RAM can run at any speed lower than it is rated just fine so shouldn't be a problem (and usually you can also lower the Voltage or tighten up the timings when running them that way)- but it is good to have the headroom of the faster speed in case you do start OCing.

Also you could just lower the CPU multiplier to 15.5 instead and that would leave you at 3.487 GHz. so just a slight overclock of the CPU instead of lowering it to 15. (lots of options and you just need to test them to find which works best for you !!) - just remember that the Hyperthread frequency and the Northbridge frequency is also adjusted with the bclk so might need to be tweaked as well to get it all stable running the bclck at 225.

I haven't had the time to really try messing with the bclk yet so not sure how picky the hyperthread and northbridge frequencies are when you start adjusting the bclk but there are seperate bios settings for them that can be lowered also (ie. changing the northbridge frequency from the 10 multiplier stock to 9 would give you 2025Mhz. with the bclk of 225 which is pretty close to the 2000Mhz. stock setting)

 

[bilbat]

Memory speed is vastly overrated (mainly, by, and for the benefit of, the memory marketers...); latencies matter, raw speed matters little; you never, ever, ever get real-world situations that do extensive contiguous transfers to/from memory (that's why 'synthetic memory benchmarks are called synthetic!) unless you're transcoding video; what you get is dribs and drabs, from here and there, each the size of a cache page, all seperated by one or the other of the latency periods!

 

[galacticman]

interesting i'm learning a lot here. According to CPU Z latency is 11 but latency was advertised to be CL8.

The SPD tab states latency as 5,6,7,8 and there's more rows of numbers i don't understand.

How do you adjust latencies in bios, is it safer to set to auto?

re: under/overclocking which method is the safest in terms of board and CPU preservation?

last night i experimented with cpu ratio and bclk. I managed to get the RAM up to 1800MHz but reverted back to normal as i got a bit scared.

I'm not as worried about the CPU being able to handle underclock and slight overclock but more worried about board. This is a bit crazy as the CPU is the most expensive part on my new build.

 

[JDFan]

The Latency you change under the DRAM configuration line on your MB Intelligent tweaker page - there will be alot of settings but you want to change the CAS# Latency, RAS to CAS R\w Delay, Row Precharge TIme, Minimum RAS Active TIme, and 1T/2T Command Timing - ( to 8-8-8-24- 1T) or (8-8-8-24-2T) if the first setting does not work for some reason - the 1T is a bit faster but some RAM has problems running with 1T.

You really do not need to worry about the MOBO unless you start upping the Voltages beyond specs as they are designed to run at those speeds and voltages (worst case the MOBO will not boot and will auto recover so you can adjust the settings - They are much safer now than in the old days when you had to set the voltages\speed settings by placing jumpers on banks of switches on the MOBO.)

 

[bilbat]

How do you adjust latencies in bios, is it safer to set to auto?

It is safer to let the BIOS set it's own latencies, assuming it gets them right! But, therein lies the rub; for some unkown reason, it often just does not work correctly... I may soon know a bit more about the ins-and-outs of this process, as yesterday, someone pointed me at a massive 'slew' of documentation regarding the physical operation of the AMD chips, as well as, apparently, large chunks of 'pseudo-code' examples of BIOS start-up routines - but, it will take a while - there's a lot of it, and I'm still working my way through the Intel 5520 docs for another possible product. CPU-Z does not do an optimum job of showing you the SPD values; I usually recommend MemSet, but several people have had it not work on AMDs, and MemSet itself seems to recommend CPU-Tweaker:
http://www.tweakers.fr/download/CPU-Tweaker14b10.zip
The trick here is to run it, and capture and post both the main screen, and the screen that appears when you click the SPD button...

If you've never captured and posted an image to the forum, there is a tutorial here:
http://www.tomshardware.com/forum/264718-30-capture-post-images-forum

 

[galacticman]

hi thank you all and for the link.

Advice here has made me a bit bolder and wiser and read today someone had increased Bclk to 2600MHz. So I figured 2025MHz would be a very safe starting point for first overclock.

I have altered BIOS 15.5x CPU multiplier 3.487GHz

Bclk 225 and altered multiplier from 10 to 9. So NB frequency 2025MHz

HT Link also 2025MHz

PCIE Clock set to 100

RAM showing 1800MHz. Advertised rating is 1.8V so I altered from 1.65V to 1.7V.

This affected graphics and system crashed with blue screen on boot. So I set RAM voltage back to 1.65V and this seemed to improve stability but got another blue screen and had to restore windows from restore mode and boot up in safe mode a couple of times.

On boot DDR3 is still stated as 1600MHz and CAS is 11 in BIOS. Should be 8 but dram frequency 900MHz

NB frequency 2025MHz


CAS 11,11,11,24

Bank to cycle rate 40
Command Rate 2T,

Ran Memtest and error message something like RAM not able to hold data.

I'm concerned I may have been sold wrong memory or it isn't what it should be.

Thank you for other links on how to post bios images. Doing such things is a bit awkard as newbuild isn't yet on the net and is a virtually bare system. I've tried to add a few test programs via usb stick.

I'd like to alter latencies but what do i alter 110ms to on DIMM 1 and 3 and 90ms on DIMM 2 and 4.

I look forward to more info and glad bilbat has a lot of technical AMD writeups to wade through.

 

[bilbat]

In keeping with the (unheard of) new AMD trend toward real-world documentation, there's a piece here:
http://game.amd.com/us-en/content/pdf/AMD_Dragon_AM3_AM2_Performance_Tuning_Guide.pdf
that may be worth a read 'in the meantime'...

 

[galacticman]

hi thanks again, sorry for delay. i've been plodding on and have only briefly looked at document.

more info 1800MHz DDR3: Memtest 216 errors at 20% coverage so i wonder could the memory be faulty?

Same memory at 1600MHz yielded zero errors at 10% coverage. So I wonder id the increased RAM speed causing more problems.

Are gigabyte boards capable of displaying memory speeds above 1600Mhz on boot up. I ask as i've increased speed to 1800MHz and 1600MHz is still displayed on bootup.

i tried to play a sample vid last night and machine crashed with a memory error but same vid played fine tonight with RAM at 1600MHz..

i tried to increase DRAM timings but did not know exactly what to put for all the parameters. (the link to the guide very useful)

most common is the 4 number sequence such as 8,8,8,24 but what parameters do you need for all the other timing parameters?

i'm getting a bit cheesed off with all the errors, bios beeps, boot failures when i alter parameters.

I've now read more of the AMD overdive guide a find it useful, particularly DDR3 timings.

boot up and shut down's slow too. it's a 3.4GHz phenom ii x4 965 with 4gb ddr3 but my old machine seems faster with 1 gb of ddr1. I think something's wrong.

the amd overdrive wouldn't install and only partially installed then stopped. So I decided to revert back to base levels with RAM at 1600MHz.

The machine performed better and AMD Overdrive installed but failed to load.

I'm thinking maybe I should settle with the 1600MHz speed even though it's apparently DDR3 1800MHz. My new build performs much better with RAM at 1600MHz and this puzzles me. CL11 I don't like though.


Best wishes

Paul

 

[galacticman]

CPU Tweaker screenshts for your perusal and comment.

DDR3 was sold me as 1800MHz cl8.

 

[galacticman]

SPD timings

 

[bilbat]

Think you've been 'hosed' by a memory company!
The only "Zeppellin" that comes to mind for me:

is this one; suggest anything??

 

[galacticman]

? are the ram timings wrong? memory was sold to me as PC14400 DDR3 1800MHz. Works at 1600MHz.

zepellin is a memory company but haven't a site in english language.