Bulldozer on 990FXA-UD5: issues with all 4 RAM slots populated

[gunite]

I know anytime I tried to underclock my G.SKILL Ripjaws X Series 16GB (4 x 4GB) 240-Pin DDR3 SDRAM DDR3 1866 (PC3 14900) Desktop Memory Model F3-14900CL9Q-16GBXL between 16xx and 1800 my HTPC rig will get random crashes related to memory. I will be in the middle of a game or watching a movie and BAM!... BSOD. Tell me that doesn't get on the nerves. The best stable settings I have gotten so far is @ 1600 CL 8 8 8 24 @1.5v using all four sticks and I haven't had a memory BSOD since I have stuck with those timings. Two sticks @ 1866 will run rock solid at profile1 timings and settings but at the expense of giving up 8gb of memory it isn't worth it in my opinion. In the real world there isn't much of a difference between a low cas latency 1600 and high cas latency 1866... Even with the high cas latency 2133 is a different story though and I would give up the 8gb but that is only my opinion
I know on Newegg GSkill has some 1600 cas 7 sticks available but I'm already vested in this setup and will wait to see if AMD changes the memory controller issues with Piledriver. Or bite the bullet and get the new Intel 2011 chip and board when, or if, it comes down in price. I have always been an AMD loyalist because of their bang for buck ratio but I really do wish they would catch up. I guess when Intel is the company setting and raising their own bar they can charge whatever inflated price they want 
Sorry for my tangent

[DarkFoss]

I've recently bought 2 *g kits of Corsair Vengence CMZ8GX3M2A1866C9R
  http://www.amazon.com/Corsair-Vengeance-PC3-15000-1866mHz-CMZ8GX3M2A1866C9R/dp/B0056KUWS4/ref=sr_1_2?ie=UTF8&qid=1322402466&sr=8-2

After a bit of tweaking I have all 4 sticks running at @ 933 MHz (1872mHz)   9-10-9-27  (CL-RCD-RP-RAS) / 41-160-2-7-14-7-7  (RC-RFC-CR-RRD-WR-WTR-RTP) reported by Aida64..will write down the exact bios settings later

Quite heavily oc'ed though on the newly released bios F7g

Seems gunite's quite correct with 4 sticks any attempt at setting the multiplier to the 9x setting and manually setting the rest of the timings would result in the bios recovery kicking in saying overclock failed resetting ram timings to 1333..2 sticks would post fine.. I guess I'm not too shocked since the earlier released Llano processors/FM1 chipset did in fact have that same limitation.

[absic]

You might want to check this thread: http://forum.giga-byte.co.uk/index.php/topic,7530.0.html that I have just posted regarding this issue.

Basically AMD have confirmed that they only guarantee speeds of 1866MHz with only two dimm's populated.

They also state that you should be able to run at the higher speeds with all four dimm's populated but that this is regarded by them as overclocking and success is very much dependant on the RAM modules being used.

[protocall]

Thanks for digging, absic.

It's nice to have an official statement, but it would have been nice for AMD to disclose this before some of us went through 3 kits and weeks of testing.

I must disagree about these speeds being dependent on specific RAM modules and/or hardware QVL lists. As this thread harps on the fact that I've tested extensively with 3 different kits across 2 brands and 3 model ranges, including those on official QVL lists, I don't see how anything but variations in the CPU memory controller could possibly be at fault. All kits produce virtually identical results. I'd love to trade CPUs with DarkFoss just to prove this. But I'm done speculating. I can live without the extra 0.5fps.

[absic]

I must disagree about these speeds being dependent on specific RAM modules and/or hardware QVL lists. As this thread harps on the fact that I've tested extensively with 3 different kits across 2 brands and 3 model ranges, including those on official QVL lists, I don't see how anything but variations in the CPU memory controller could possibly be at fault. All kits produce virtually identical results.

Yes, I have to say that I personally agree with your sentiments and am more than a little sceptical of the official AMD stance regarding this. But hey, didn't they do the same thing with the Phenom CPU's so why are we all so surprised by this?

After the fiasco with the memory controllers on the Phenom ii CPU's and the hours I spent getting to the bottom of that particular issue, I decided not to rush into getting a Bulldozer processor and from the early reports I'm pleased that I didn't. That said, I will get one at some point in the future, once some of the bugs are ironed out a bit more, but I won't be getting a large amount of fast RAM whatever they say.

[protocall]

But hey, didn't they do the same thing with the Phenom CPU's so why are we all so surprised by this?

I can agree. But by that logic, one could also argue that after going through the same thing with Phenom, AMD should have learned to share the fine print with the enthusiast market to avoid another negative feedback debacle. I'd suspect any similar limitation in the server-destined Interlagos chips built on the same arch is disclosed or discussed in every enterprise customer meeting, as those folks would be slightly less tolerant if they spent the extra money on RAM only to find it "isn't supported".

Personally, I skipped the Phenom/AM3 generation. I have a few AthlonII Kuma/Lima/Sparta machines still kicking with 4 DIMMs, albeit at the old DDR2 days of 800MHz. I keep up with the tech regardless and read about all the memory controller limitations in AMD arch shared across these generations. Then I read that Bulldozer's brand new core design also contains a redesigned memory controller, supporting up to 1866. Then I buy a board with 4 DIMM slots that supports up to 32GB total and speeds well in excess of 1866 if overclocking.

Perception is reality. Given the above, in the words of Denis Leary, "What would you think? I think you would think what I thought!"

Good luck to you when you buy a Piledriver core!

[gunite]

I now have all four sticks running @ DDR3-1866. As far as CPU OC I left that on Auto and selected profile1 but I manually installed ALL memory timings. It works like a charm now... BTW for those of you that like Windows Experience Index scores here it is.... Ready?....16gb of DDR3-1600 CL 8 8 8 24 is a score of 7.6. 16gb of DDR3-1866 CL 9 10 9 28 is a whopping score of, hold onto your hats, 7.7. But we all knew the difference between the two scenarios was marginal at best right

[04ahgy]

Hi all!

A quick question. Please answer it if you know it 100% sure. The question is about EFI. EFI could be configured to have GUI or also can be configured to look like the classic way. This is fact.
GA-990FXA-UD7 uses EFI (that looks like classical BIOS) or it uses just the good old AMI BIOS?

Thanks in advance, HGyu

[DarkFoss]

I now have all four sticks running @ DDR3-1866. As far as CPU OC I left that on Auto and selected profile1 but I manually installed ALL memory timings. It works like a charm now... BTW for those of you that like Windows Experience Index scores here it is.... Ready?....16gb of DDR3-1600 CL 8 8 8 24 is a score of 7.6. 16gb of DDR3-1866 CL 9 10 9 28 is a whopping score of, hold onto your hats, 7.7. But we all knew the difference between the two scenarios was marginal at best right

I'm jealous you can use profile1..my system won't post after applying it even after manually adjusting the timings afterwards..although I haven't tried it since updating to bios F7g..My Windows  Experience Score is 7.8 on the cpu/memory..holding me back from a perfect 7.9 across the board :p