Machine runs fast with 16GB but dreadfully with 32GB

[tricky]

in this case sounds like it could be the memory controller on the cpu.. youve maybe got some instability when its being stressed .. you could try manually upping the voltage to the ram, or the memory controller (not advisable) or to test, downclock the cpu/ram..

With regards to instability when stressed, we haven't even got to a point where we are stressing the machine - it is literally after logging in where the windows desktop icons takes a minute or two to load in.

Upping the voltage on the ram: can you suggest what value I might try? It is set to the default 1.5V.

Underclocking the RAM: do you mean simply drop the MHz (the multiplier) to its lowest setting? I think the minimum is 8x (so I guess that is 800MHz).

Underclocking the CPU: is this just the muliplier on the CPU? The default is 35x (I think Turbo is on and will up it to 38x or 39x if it feels necessary). Should I set this to 20x (for instance)?

[super gnu]

when i said stressed, i meand by dealing with a full deck of ram. im guessing really but with the older i7's for example, you couldnt overclock as high with all the ram slots full as it puts more strain on the memory controller the more ram you have.

wrt the other questions, short answer is do everything by small amounts! you can try dropping the cpu multiplier and/ or the memory multiplier as far as you want but itll only tell you its more likely a cpu problem.. voltages wise.. edge them up by small increments, keeping an eye on temperatures. go from 1.5 for the mem to 1.52 , 1.54, 1.56 etc etc.. dont go much higher than 1.6v.

ive never changed the voltage to the memory controller personally, but in my bios at least, its possible. might be an avenue to try.. with more obscure voltage multipliers like this you have to expect some issues if you change too much.. quite sensitive.

a general cpu voltage boost ( 0.05v for starting example) might also help..

[Donald2B]

I've had many motherboards come to a crawl when filling up all memory slots. Yes it is very frustrating to say the least.

Have you contacted Gigabyte about your issues? If you haven't, you should! You are rapidly reaching a point where your problems could be hardware related and new hardware may be needed to fix the problem.

Also start scouring hardware forums to see if anyone else has had the same issues with your motherboard. Maybe they found a workaround or a fix that got them up and running.

[alexyork]

Have you spoken to Gigabyte yet?

[tricky]

Nope. Mainly due to lack of time, but I dread the prospect of running through things with them as I've lost track of exactly what has been done and when. Once a few projects are out of the way, we will try to make contact.