Rampage Extreme X48 LGA775 socket

[agent_x007]

1) Yes you can use 4x4GB of memory on X48/X38 (example for DDR3 : https://valid.x86.fr/y81fa8)
a) It needs to be dual ranked (memory chips on both sides of the PCB)
b) It needs to be "Intel compatible" for DDR2 memory
c) Intel compatible 4GB DDR2 non-ECC (and NOT Reg.) DIMMs are WAAY too overpriced for them being an actual option for 99% of LGA 775 users
2) P35/P45 should be the same. Newest BIOS may be required, and high tRFC values (100+) will be needed for high frequency stability on high capacity modules (not all boards have that).
3) 8GB DDR3 DIMMs will NOT work on consumer grade LGA 775 boards.

 

[RJARRRPCGP]

And I seemed to need 1.90 V for only 333 Mhz/(667/666) (For 8 GB total with all slots filled) Even when I upgraded to P45, when using all those RAM sticks, I never set it to less than that for DRAM voltage.
I never got an X48 motherboard, sadly. Are they worth getting for people with P45?

 

[Disier]

hi there... about memory issue got on my Asus Rampage Extreme 775 mobo with 2xGB Gskill F3 12800CL7 1600 1.9v. Timing 7-7-7-18
As was advised i bought a Corsair KIT CML8GBX3M2A1600C9 1.5V Timings 9-9-9-24.
When i try to boot with just 1 sitck 4GB system won't boot... any advice??? i tried to clear CMOS... no sucess...
might these model be no match with board???

 

[agent_x007]

Could you provide a photo with underside of the heatspreader (where memory chips sides can be seen), or can you check with flashlight if memory chips are on both sides of memory module ?
Can't find spec for those : CML8GBX3M2A1600C9
Or did you mean : CML8GX3M2A1600C9 ?

PS. Better check this RAM in newer DDR3 platform, to see if they work on it.

 

[Disier]

hi there. thinks for reply yes i believe i refer wrong model is CML8GX3M2A1600C9. here are some pictures... still have some doubts about dual side memorys but i believe this ones are...

i tried to boot with one of my modules and one of new ones... system does boot but only recognizes gskill module... tried to raise dram voltage in ram to 1.65 the same....

Would i get better chance with these modules CMX8GX3M2A1600C9 XMS3? They work at 1.65v.... probably will return these for XMS3 ones...

​

 

[agent_x007]

Try looking from underside.
This is how Dual sided DDR3 memory module looks like.
With Single sided one, thermal pad would be touching PCB directly (no gaps) on one side.

 

[Disier]

Thanks for reply! I got it now well in that case they do are double sided not best picture but there are 2 gaps on both side os chips....

meantime one small detail... before getting these corsair kit i asked a friend of mine that has some modules around and i tested with a XUM 4G DDR3 1600MHz PC3-12800 Non-ECC Unbuffered 1.5V CL11 witch i didn't ever heard of and one single module system booted and recognized the 4GB! And these are DR3 1600MHz PC3-12800 240pin DIMM 1.35V – 1.5V Voltage CL11.
How the hell with these voltages and so it boot and with Corsair ones fail????

 

[agent_x007]

I think you are holding a Single side stick there... only "bottom" side has stuff on PCB, while "top" side is empty.
Try to put it on table close to background, that way - camera can focus easier on tiny details inside (use manual focus).

 

[Disier]

Hi there. Going to try take other picture but even so is it mandatory that modules are double sided for system to recognize 4gb? Becouse the Xum module i tested didn't even had pcb around was a single dim for sure low profile and it worked...

 

[agent_x007]

It's not limited to 4GB, 8GB modules will behave the same way.
I don't know of any 512M/chip DDR3 modules that work with LGA 775.
AFAIK : It must use 256M/chip (ie. low density), or less to work.

Short version :
Works with LGA 775 : 16x 256M = 4GB (16 = 8 chips x 2 sides) or 8x 256M = 2GB.
Does NOT work with LGA 775 : 16x 512M = 8GB/8x 512M = 4GB.
^I'm assuming you are not using server grade memory and/or motherboards.

 

[Disier]

Hi again friend. Thanks for your help first. Got a litle lost on those numbers there. Botton line board is a original asus rampage extreme with last bios 1301.

Then according to your link a few posts htttps://valid.x86.fr/y81fa8 you used CMX8GX3M2A2000C9 right?
The ones i bought are CML8GX3M2A1600C9 witch i believe are quite similar.
I am not even aiming at 2000mhz i would be happy with stable 1600 or even 1400mhz for daily use...
Question remains what best 4gb module would i get better chance of working? And then go from there to at least 12gb or 10gb i think one of my board slots is faulty...

Here is link for ones i bought https://www.corsair.com/pt/pt/Categorias/Produtos/Memória/Memória-de-alto-desempenho/Vengeance®-Low-Profile-—-8GB-Dual-Channel-DDR3-Memory-Kit/p/CML8GX3M2A1600C9#tab-tech-specs

I do believe you are right only one side has chips on it so these are not double sided... it that the problem? Where the ones you used CMX8GX3M2A2000C9 double sided??

Meantime i did got an awnser from other forum https://www.overclock.net/threads/i...atible-for-intel-p45-p55-h55-x38-x48.1775421/ stating that https://www.gskill.com/search?keywords=f3-10600cl9d-8gbnt G.SKILL-F3-10600CL9D-8GBNT 2x4GB are indeed a match with X48 chipset...
probably better luck with these ones...

well new info.... i was advised to stick with modules branded has "value ram"... better chance of getting those to work!

 

[agent_x007]

Yes, RAM I used from that link is double sided.
I think (with time), manufacturers just swap lower density chips with higher ones, to get things done cheaper.
It doesn't make any difference on newer platforms, but you are left hangin' with oldest platform (like LGA 775).

Tricky part :
Externally - all modules can be the same (spec/visually), and only difference shown will be a different "rev x.y" on sticker vs. double sided older version. If that's the case, unless you check underneath (like we did), you can't be sure if module is double or single sided.
It's not done this way usually (you should get like "S" in model to indicate a single side version), but sometimes manufacturers simply are lazy