extra ram causing system instability

iToke · 15 Sep 2011 at 08:44

Hi guys,
I have an overclocked i5 750 PC (running @ 3.36ghz) with 4GB (2x2GB) of corsair XMS CMX4GX3M2A1600C9 memory running at 1600mhz instead of 1333mhz.

I just bought another 4GB corsair kit (exactly the same) to give me 8GB total ram. When I added the extra ram my system became very unstable, BSOD's, failed boot attempts etc.

Not sure what I have to do to make my system stable. I have a great power supply (800w OCZ extreme), a corsair H50 water cooling kit on a Gigabyte P55 UD4 motherboard. I've updated the BIOS to the latest version and I'm using Win7 64bit SP 1

any thoughts?

thanks

SupermotoMX · 15 Sep 2011 at 09:02

try backing off your overclock / increasing ram volts (not over the maximim)

or maybe slacken the ram a notch or two

iToke · 15 Sep 2011 at 09:27

SupermotoMX said:
try backing off your overclock / increasing ram volts (not over the maximim)

or maybe slacken the ram a notch or two

Thanks for the quick reply, I'm new to overclocking (my first attempt) how do I know what the max ram volts are?

SupermotoMX · 15 Sep 2011 at 09:41

a quick google tells me its 1.65volts but it should say on the side of the ram sticks / original packing, make sure you change the volt in the bios as if you have left it on standard it could be at anything from 1.5v - 1.6v (which wont be enough)

edit: you also want to make sure you set the timings correct, (9,9,9,24) if it is still causing instability try making them 10,10,10,27 and if that doesnt fix it there is a motherboard problem somewhere

edit2: make sure you are trying this without the overclock so you can troubleshoot which is causing the issue better

iToke · 15 Sep 2011 at 10:12

Thanks again SupermotoMX.
I've uploaded an Everest report of my overclock & memory details here

If the only way of having 8GB of ram instead of 4 means I have to return all my BIOS settings to standard i.e not overclocked, what would be better - an overclocked PC with 4GB of ram or not overclocked but with 8GB of ram?

I mainly use my PC for web development, so I often have Dreamweaver, Photoshop, Illustrator & web server software open at the same time and I also use it for gaming & watching HD movies.

If I get things wrong, can I cause serious damage?

Cheers

SupermotoMX · 15 Sep 2011 at 10:55

i have heard of some motherboards needing more NB voltage to support become stable with all of the ram slots filled, however im not 100% on this so it would be better to wait for someone with more knowlege

edit: but for short term, i think 8 gigs of ram would benefit you more than a higher cpu clock

iToke · 15 Sep 2011 at 11:25

Just checked my BIOS, the ram voltage is set to auto (1.5) will have a go a tweaking it later when I've got time.
Thanks for all your help.

Plec · 15 Sep 2011 at 11:49

The memory controller is in the chip itself so i'm afraid you can't tweak the NB like the old generation of chips - but there are other settings you can try.

Ideally when a system is overclocked you should set the memory up manually and if you're having problems settiing up 4 sticks you should set everything back to stock/default settings until you manage to get the system stable - and then reintroduce the clock.

I would save a profile of your present settings in the BIOS (or take photos of screens) and then set the memory up mannually:

Command rate - 2T
Timings - 9, 9, 9, 24
Frequency - 1333MHz to start with but then i would bump it up to 1600MHz once stable as frequency should not effect stability if the sticks aren't corrupt.
As you're having stability issues use the full 1.65V

If you can get things stable then you can slowly introduce your clock.

If you can't get things stable you will need to memtest the new sticks and try to ascertain if it's a memory problem or a DIMM slot problem.

iToke · 15 Sep 2011 at 12:33

Thanks Plec, just downloaded Memtest.
Will post my results later.

Great forum by the way, nice to have quick, knowledgeable replies!