AM3 RAM OC?

[Noxinite]

I've been playing with my hypers on a Crosshair IV using a 555 BE, and it refuses to POST at higher than 244MHz bus with the 1:4 RAM divider. The funny thing is that it is fully stable at 242MHz bus with 1:4, and the lower ram dividers work at the higher bus as well.

I did find some stuff on this forum about enabling ECC on non-ECC ram and that was supposed to help mem OC, but when I quickly played with it, it didn't seem to help.

So the question is, anyone have any tips for getting higher ram clocks working? Or do you just need a Thuban IMC to push higher?

Edit: I forgot to add that I've tried PSC quickly as well as newer/older BIOSes, but no real difference there.

Edited September 16, 2018 by Noxinite

[yosarianilives]

21 hours ago, Noxinite said:

I've been playing with my hypers on a Crosshair IV using a 555 BE, and it refuses to POST at higher than 244MHz bus with the 1:2 RAM divider. The funny thing is that it is fully stable at 242MHz bus with 1:2, and the lower ram dividers work at the higher bus as well.

I did find some stuff on this forum about enabling ECC on non-ECC ram and that was supposed to help mem OC, but when I quickly played with it, it didn't seem to help.

So the question is, anyone have any tips for getting higher ram clocks working? Or do you just need a Thuban IMC to push higher?

Edit: I forgot to add that I've tried PSC quickly as well as newer/older BIOSes, but no real difference there.

AFAIK the limit on deneb based chips is around 1866ish and the limit on thuban based chips is 2133ish. To help your mem you obviously need to adjust cpunb voltage as this is also for the chipset, although you also don't want to punch it as it can have negative scaling. The range is 1.3-1.55v. On ambient probably best to be sub 1.5v or even 1.45v.

Also I've found that a voltage named vddr (not familiar with civf bios but this is present in cvf bios) can help at times. Not sure how it can be set safely on ambient but on ss it helped to max it (around 1.8ish). 

Also I'm sure that you're already running your hypers at 2v but always a good thing to remember, am3 "Ddr3" controller may as well be ddr2 controller as far as voltage tolerances so you can shove as much volts as the mem continues to scale to. (usually 2v for hypers on ambient) 

Not sure if this helps but I hope its useful. 

[Noxinite]

So far I've found that none of the voltages really moved the ram freq wall, but NB (not CPU NB) helped stabilise settings that you could already POST at. The wall was the same for 8-8-8 and 6-7-6, so definitely not the ram being an issue. I also didn't need them for stability at what I could POST at.

Moving to the inner slots allows me to POST at higher freqs, but is then unstable at the tighter timings that the outer slots could run.

When I put the CPU on phase quickly the ram freq I could POST at seemed to increase a bit, but not massively. More testing needed here as ram timings and voltages seemed to make a bit of difference.

I also found that bioses 3027 and 3029 (Crosshair IV Formula) allowed higher ram freqs to boot, but they also had an issue where they would fail POST at any setting until you loaded defaults, rebooted and reset the same settings. So I moved to 2101 for initial testing.

Edited September 16, 2018 by Noxinite

[TaPaKaH]

RAM walls at 920-940MHz are absolutely normal for Deneb and there is nearly nothing you can do about it. Some newer boards like 990FX can do a dozen MHz more than 790FX but it won't give you a noticeable difference, especially that newer chipsets tend to be a little bit less efficient at the same clocks.

[Noxinite]

Bah, that's no fun.

But good to know I guess,.

[TaPaKaH]

The whole "fun" of that platforom is supposed to be its simplicity

[George_o/c]

I had a blast back in the day with 955BE and Giga 890FX UD7 plus some Hypers My scores from XS low clock challenge are not visible anymore because the photos don't exist, but I vividly remember the NB topping at 3100MHz @ 1.45VTT on air. Also my best scores were done at 890-900MHz RAM @ 6-6-5-17  

We discussed a lot with chew* back then and he was telling me that for Thuban the best RAM are PSC, because you can push 1100MHz 7-9-7 for example. 

Bus speed was lower, maybe about 225MHz. I remember some scores at 260MHz but I had a very hard time getting the CPU up there. 

Edited September 16, 2018 by George_o/c

[Noxinite]

1 hour ago, TaPaKaH said:

The whole "fun" of that platforom is supposed to be its simplicity

Eh, I like having things to tweak and improve results.

1 minute ago, George_o/c said:

I had a blast back in the day with 955BE and Giga 890FX UD7 plus some Hypers My scores from XS low clock challenge are not visible anymore because the photos don't exist, but I vividly remember the NB topping at 3100MHz @ 1.45VTT on air. Also my best scores were done at 890-900MHz RAM @ 6-6-5-17  

We discussed a lot with chew* back then and he was telling me that for Thuban the best RAM are PSC, because you can push 1100MHz 7-9-7 for example. 

Yeah, I had a Thuban result from 2 years ago with 2100 7-9-7 32M stable, but couldn't remember if that was just a Thuban thing as I sold that chip.

 It could do 3.4GHz NB on 120mm AIO - I regret selling it now.

[George_o/c]

Oh I found chew's run at 1100 7-9-7 with Thuban, I remembered correctly

[I.nfraR.ed]

That's correct - 960 6-6-6 is the feasible maximum with Deneb and needs really good IMC. I've done 1000 on one sample too, but wasn't stable and usable no matter the timings.

For Thuban PSC is the way to go (maybe BBSE would be good too, not sure), especially full pot where its IMC gets picky. chew* told me that and I've experienced the same.

Controller doesn't care about vDIMM though, however I've never needed 2V+ on my GTX2's to maximize timings on this platform. IIRC it used to be in the 1.85 - 1.9V range.

But my set is very good, I think.

[Bullant]

I've only tested one board and one CPU ahah but cold CPU helped my mem freq scale for sure with my CPU...can't boot the higher mem strap on CPU air.....For me my hyper, board ,CPU is around 930mhz and did real quick test on PSC cold and it ran 950mhz 6-7-5-15-11 

 

My hyper runs were only 1.77v , PSC cold was 1.83v....when I tried 1.8v hyper I don't think it liked it for me....tho I'll try higher later to be sure.I have thuban on the way to try.....

[yosarianilives]

13 hours ago, Bullant said:

My hyper runs were only 1.77v , PSC cold was 1.83v....when I tried 1.8v hyper I don't think it liked it for me....tho I'll try higher later to be sure.I have thuban on the way to try.....

Interesting, I've always run my hypers at 2v on am3 and they seemed to like it. Was able to do 1760 6-6-5-22 1t that way with hypers on air, cpu on ss. Although lately my cvf has been unhappy with high vdimm so perhaps there's something to lower vdimm.

[Noxinite]

I already told you, 2V for long periods of time is not good for hypers. I have 2 sticks that have become dead/degraded after something like 0.5-1 year.

While you're all here, is it just me or does base clock jump around a ton for anyone else? Like +/-2.5MHz. About as bad as Z170/Z270 for trustworthy low clock results, if not worse.

Edited September 17, 2018 by Noxinite

[Splave]

Hey my board doing that fail boot thing too. So fun to pass pi then fail to boot when you restart and need to clear and reapply Saber tooth 

[Noxinite]

Best ambient so far at 4GHz (+/- bclock movement):

Not sure of effi or anything atm.

[I.nfraR.ed]

1 hour ago, Noxinite said:

Best ambient so far at 4GHz (+/- bclock movement):

Not sure of effi or anything atm.

About 15-16sec off.

[Alpi]

Mine is very close !

http://hwbot.org/submission/3678064_alpi_superpi___32m_phenom_ii_x2_555_be_16min_31sec_719ms/

[Alpi]

Don't really like psc with this platform. I prefer hypers. Those chips have some specific what made them very good for Am3. I like these cpus, You have more than one way to improve eff. With later bios (what is for Fx cpus too) I was able to set ram freq spectacularly higher but at the cost of latency so I can't move forward at all. 

Edited September 18, 2018 by Alpi

[Alpi]

On 9/17/2018 at 6:21 PM, Noxinite said:

I already told you, 2V for long periods of time is not good for hypers. I have 2 sticks that have become dead/degraded after something like 0.5-1 year.

While you're all here, is it just me or does base clock jump around a ton for anyone else? Like +/-2.5MHz. About as bad as Z170/Z270 for trustworthy low clock results, if not worse.

Cr IV does that clock moves at me too. It's tricky to stay between the 5 ghz low clock barriers. At that high it causes pretty big cpu clock fluctuating.

[Bullant]

18 hours ago, Splave said:

Hey my board doing that fail boot thing too. So fun to pass pi then fail to boot when you restart and need to clear and reapply Saber tooth 

Lol....that would be annoying 

[yosarianilives]

Perhaps sabertooth boards just have issues? This last weekend on sabertooth we were having issue across multiple cpus, am3 and am3+, where it had a CBB at -80c. Basically you could boot into bios, pull down, then boot into OS. However if it failed to run the settings or you needed to reboot from the OS you would need to pull up to around -80c to get it to POST at all.

[Noxinite]

Full pot to -80C, outch...

[yosarianilives]

Yes, wasted a lot of LN2 troubleshooting last weekend it before we determined that it was a board issue.

[Splave]

guess the crosshair is worth the premium  

[yosarianilives]

1 hour ago, Splave said:

guess the crosshair is worth the premium  

Eh my cvf forgot how to mem. Was having issues running higher vdimm or running good mem settings for the past month then this last weekend it started refusing to post with any mem. It seems that boards just wear out after a while. Got many good SS sessions out of my cvf before that though, and my understanding is that sabertooth had done very well in a few ln2 sessions before it became a dice only board.