Buying RAM

[Mitch Simon]

When I purchased my computer about, WOW, 2 years ago I unfortunately bought 16GB of incompatible RAM for a Asus Sabertooth 58x MOBO. I am looking to buy 16 GB of the correct RAM. Looked up what is compatible to the board and came up with (Corsair CML16GX3M2A1600C9 - Vengeance Low Profile 16GB (2 x 8GB) )

Any suggestions on what not or what I should be aware of? Just want to make sure I don't run into the same mistake.

[Kat]

How was it not compatible? Speed? Wrong type?

[Mitch Simon]

I dont have the ram in front of me but the Sabertooth x58 had a list of compatible ram. The number on the ram I bought was not in the listing.

[SteveC]

I am no expert Mitch, but the memory will have a code more in this format "PC2-5300 FB" for instance, that's what I have. My machine takes PC2-5300 FB memory, any PC2-5300 FB memory I buy will work for sure.

Yours can take DDR3-1866 and DDR3-1800 in fact. This is the codes your looking for, this stuff should work.

I found this your MOBO manual, see page 30 its got a list of compatible memory. http://dlcdnet.asus.com/pub/ASUS/mb/LGA ... th_X58.pdf

I cannot gtee that any DDR3-1866 or DDR3-1800 will work for sure, in the world of gaming memory people are looking for max performance so maybe you can still run into trouble I don't know - I never had gaming memory myself - but that 'Timing Label' in the manual p30, that is what that relates to performance. But you can see a list of compatible memory in that pdf, there is a few for corsair there.

Mabye this is of use, sorry if you know all this already I never had a gaming PC

Edit: Micth! That CML16GX3M2A1600C9 stuff is 1600mhz, I think u want 1800 or 1866 I think. Don't go and buy anything of the basis of this advice! Tell me what blocks of what size memory (ie 4x 4GB, 2 x 8gb etc) to you want perhaps I can point u to something.

[MarkF]

Mitch post the RAM details you bought, just because it is not in the list does not mean it won't work, as long as it is the correct DDR type and your mobo supports the voltage it should work, there are a few other things but very rare to encounter. Basically you may need to update the BIOS for your mobo to set the timings correctly, if as Steve says the timing is 1800 anything quicker will be down clocked to that and anything slower will just run slower.

But I am the sort of person that would just sling it in and see what happens

[Mitch Simon]

Thanks Guys, I really appreciate the help.

My RAM Details are:
Corsair XMS3 DDR3 1600 MHZ 6GB (3X2GB)
9-9-9-24 @ 1.65V Ver2.3A
CMX6GX3M3A1600C9

According to the manual the RAM that I have is not in their listing. The closest Corsair RAM @1600MHZ is a CMD4GX3M23A1600C3XMP, timing 8-8-8-8-24 @ 1.65V.

I am not familiar with flashing my BIOS so I did not attempt to do that. I just bought some RAM, installed it and assumed I would be good to go. The only amount that shows in my OS is 4GB with 3 sticks at 2GB which should give me 6GB. When I put the other 3 sticks in for a total of 6 for 12GB it still shows 4GB. Thats why I assumed the compatibility is incorrect. Should I be looking at something else, like the timing?

BTW, if this does turn out to be the wrong RAM, I will have 12GB or RAM for sale Dirt cheap!!!

[MarkF]

Okay, when you put all six sticks in how much Ram shows in the BIOS when it posts?

Are you by chance using a 32bit version of Windows? Only a 64bit version will show more than 4GB of RAM.

[MarkF]

There is the informative bit from your manual on page 2-11

[SteveC]

Yes it could be a 32 bit thing - 32 bit systems can only use 4gb no matter how much RAM is actually there.

But more likely I am afraid Mitch, I see you put in 3x2gb. Well, in my experience you have to put in RAM in pairs mate. It's just the way MOBO's work. It has to be 2 or 4, if you put 3 the 3rd will not work until it has a 4th to pair with.

[MarkF]

Yes it could be a 32 bit thing - 32 bit systems can only use 4gb no matter how much RAM is actually there.

But more likely I am afraid Mitch, I see you put in 3x2gb. Well, in my experience you have to put in RAM in pairs mate. It's just the way MOBO's work. It has to be 2 or 4, if you put 3 the 3rd will not work until it has a 4th to pair with.

Not all mobo, one of mine is triple as I believe Mitch's is, such RAM configs went out of favour though, but putting in 6 sticks will not get the same speed benefits as triple, also different timings is not as efficient either, but TBH performance increase is negligible compared to an over clock.

[Mitch Simon]

Ok this is where I'm at and thank you guys again for the help. BIOS System Info shows only 4088 MGB. So I DL CPUZ to see if is registering and it shows that I have 12GB installed but it still shows 4GB in OS. Here is the link to my CPUZ varification; http://valid.x86.fr/hjtxvm. I am searching the web to see if it is something I didnt do when I installed the RAM.

Here are my system stats:
| CPU: Intel Core I7 950@350Ghz | GPU: ATI Radeon HD 6890| MOBO: Asus Sabertooth x58|
| RAM: Corsair XMS 4GB DDR3 @1600 @ 1.65V | OS: Win7 Premium 64 bit | Wheel: Logitech G27
| Triple Screen Dell 24inch Monitors

[Ray Walton]

Well I think your problem is most likely in the BIOS settings if your have followed all the above good advise and info. Certainly with my old Mobo I have to enable in the BIOS, the Remap Memory Feature option in the Chipset Configuration settings under the North Bridge configurations, as without that enabled then even with Windows 8.1 64 bit OS it will only see 4 GB of my installed 8 GB of DDR2 GSkil RAM. Of course I have it enabled and see all 8 GB of RAM in my Win 8 64 Bit OS. Cannot be sure you will have this BIOS setting option with your far more recent Mobo, or it may be named differently, but well worth a check with the symptoms you are describing.

My Mobo is now an 8 year old Asus P5B-E socket 755 board with what was back then a high spec top rated Intel Core2 Duo E8400 cpu over-clocked safely to 3.61GHz per core and with a good modern Asus R7 260X-DC2 GFX card, which once again is suitably and safely over-clocked when it auto switches to 3D gaming mode. This combo gives me very fast performance for all my software including rF2 and iRacing as well as my photography processing aps like PhotoshopCC 2014 and Lightroom 5. SO as I keep saying I see no point in upgrading this perfectly good fast system which still impresses me with its performance.

The message is though that getting the BIOS settings right and with safely and thoughtfully over-clocking where you can, does make a huge difference to performance. My overclocked and optimised system out performs many of my friend's modern quad core systems which have NOT been BIOS and OD optimised, and/or have way too basic GFX cards and insufficient memory installed. So Mitch I have to say there are many websites there to teach you all about BIOS set ups for your system just Google them and put in a few days worth of study, it will pay dividends for sure. Tom's Hardware site is a good place to look for starters.

There are many quite complex areas of over-clocking settings too, like the DRAM clocking works usually on what they call form memory something like clocking ramps and to optimise this you need a setting that is at the top of the best ramp you can use before it drops back down to start another clocking ramp that will end up too fast for your system and DRAM. All to do with basic FSB clock speed and the multipliers used. Anyway don't worry about all that just yet but I am was just illustrating how much you can learn with some reading and a little well applied thought, as understanding is far better than parrot fashion following otherwise confusing steps I find.

Good luck with it Mitch and hope that helped a little for you so you can now see and utilise all of your installed 8GB of DDR3 DRAM.