DDR3 Ram Speed for overclocking AMD 1075t

[rodgerdodger]

Bit confused about ram speed,

the 1075t states maximum ram speed of 1333Mhz, im presuming thats the no overclocked rate of 200Mhz FSB .

So i purchased this speed ram thats its in the QVL for my mobo, Thing is i cant seem to push past 3.8Ghz without BSOD (blue screening in Prim95 in like a second) or the DRAM light coming on the mobo. Ive tried over and under clocking .

I noticed other people with this CPU for OC past 4Ghz are using faster ram. So should i get faster ram like 1600Mhz? or is something else going wrong? any help would be greatly appreciated.


SYSTEM
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MOBO: ASUS M5A97
CPU: AMD 1075T (non black edition)
RAM: G.SKILL RIP JAWS DDR3 1333MHz 9-9-9-24 1.5V
-----------------------------------

* disabled all features such as turbo core, spread spectrum etc.

* set ram timings- 9 9 9 24

* set CPU and Ram voltages both to 1.5V

* set set Ram frequency to the lowest ratio, ends up being about 1080Mhz

* set HT and NB freq to be closest to 2000Mhz, from the options available ends up being about 1890Mhz

Everything else is pretty much Auto

 

[lowjack989]

RAM with higher clockspeed does allow for OCing headroom so your assumption is right...I use 1600 MHz for all my rigs ....It allows you to up the FSB, if needed during OCing....Check these pics out on FSB OCing result vary of course but it give you a basic look at how to get it up there...Not all BIOS are the same I realize that this is just showing some basic settings and what to look for.

Mind you I am using 1600 MHz DIMM's ...I highly suggest getting at least CAS 7 1333 MHz as that will allow you to loosen timings on the RAM to get it OC'ed up above 1333 MHz ...Take note of the voltage setting this is very important to take note of as it will increase the heat output of the chip substantially...OC'ing..requires an aftermarket cooling solution which since you are attempting to OC I assume you already have...According to my calculation your FSB is up around 252-255 MHz if that is the case your RAM is OC'ed quite a bit...Your settings to get to 3.8 on that chip would have to be something like this:

Multi.(locked): x15
FSB: 253 MHz
RAM:1686 MHz (way above SPD)
Voltages I assume you left on AUTO

 

[rodgerdodger]

awesome thanks for info. would i be best getting the faster ram my mobo can handle with cas 7 as it can be underclocked

despite the face the 1075t says it can only handle ddr3 1333Mhz

 

[lowjack989]

It will handle what ever your MOBO can handle...That is just the limit of how fast the IMC tranfers data thats why a lot people say just get 1333 MHz and no faster...Yet when OCing higher speed RAM allows for the FSB to be raised higher due to the RAM's ability to accomplish faster speeds...

 

[rodgerdodger]

sweet makes perfect sense, legend

 

[rodgerdodger]

tested out some faster ram , same sorta of problems, i can get it stable at 255FSB now and thats it, any more and i get blue screens. Anything i should do with HT or NB freq or voltages?

Heres current settings, stable and running cool at 41 in prime 85

http://i.imgur.com/fWMmL.png

 

[lowjack989]

That is probably the boards limit

 

[rodgerdodger]

got it going a bit faster read somewhere that NB should be 3 x FSB speeds, which did the trick. at 4005Mhz

FSB:267
Multi:15

 

[lowjack989]

Good deal..glad to see you got it going