[ GA-EP45-DS4 ] Memory & MCH problems

[FragassRock]

Hi everyone,

I recently bought a Gigabyte GA-EP45-DS4 motherboard and a C2Q Q6600. Before I had an Asus P5B and a C2D E6400.

On the previous system (P5B) my ram 2 x TWIN2X2048-6400 ( 4 x 1G written 5-5-5-12 1,9V, SPD 5-5-5-18 ) @ 800Mhz worked flawlessly.

On the new system (GA-EP45-DS4), DDR2 at 800Mhz freeze happens under heavy load. I verified with OCCT RAM test and every time it freeze between 2 and 5 min after the test beginning.

- I tested with the sticks with memtest and had no problem.
- I tested each dual sticks separately OCCT and it freezed.
- I tested different bios settings every time at 800Mhz (Strap 3,00 x FSB 266):
- Memory [auto], VDIMM [auto], Memory enhancement [Turbo].
- Memory [auto], VDIMM [auto], Memory enhancement [Standard].
- Memory [auto], VDIMM 1,8V Memory enhancement [Turbo].
- Memory [auto], VDIMM 1,9V Memory enhancement [Turbo].
- Memory [auto], VDIMM 1,940V Memory enhancement [Turbo].
- Memory [auto], VDIMM 1,960V Memory enhancement [Turbo].
- Memory 5-5-5-12, VDIMM 1,9V Memory enhancement [Turbo].
- Memory 5-5-5-18, VDIMM 1,9V Memory enhancement [Turbo].
- Memory 5-5-5-18, VDIMM 1,9V Memory enhancement [Standard].
- Memory 5-5-5-18, VDIMM 1,960V Memory enhancement [Standard].
- I tried to modify the MCH voltage from 1,10V to 1,14V
-> Every time it freezed the system (hard reset needed) under OCCT RAM Test.

- Then I modified the strap to 2,50 x 266 FSB (so the ram is underclocked at 666Mhz) and then the OCCT RAM test passed seamlessly!!!

Having read some information on the official Corsair board it seems that when using 4 sticks you need to lower the FSB (but as written before my system don't work with only 2 sticks).

So I decided to buy new sticks and I choose OCZ Reaper PC8500 2x2Go 5-5-5-15 1066Mhz @ 2,2V. And after installed them on the mobo re-configured all in [auto] in the bios. I started another OCCT RAM Test and... Tada it FREEZE.

I tested every ram stick in single channel and It worked! OCCT RAM Test did not freeze. Dual Channel problem?

So I put the two sticks in place, returned in the bios and tried to another bunch of settings. Increasing MCH and RAM voltage and write every memory setting manually with values read with memset. Nothing worked every OCCT Ram Test freeze the computer.

During my tests I observed something very strange : Increasing MCH Voltage result in faster freeze in OCCT RAM Test. So I dumbly LOWERED the MCH Voltage to 1.0V and you know what?

-> OCCT Ram Test passed seamlessly! I tested 0.9V but the system did not even boot. The only value working and possible under 1.1V is 1.0V not very tweakable...

So in order to work all ram settings must be set manually, static tRead set to 7 for each channel, XMP disabled, performance enhance for RAM to standard and MCH core voltage to 1,0V!

So do you think it's a board problem, bios read voltage problem ? Do someone has the same problem than me? Do you think that it could be corrected by an upcoming bios update?

PS : Sorry for my english 'cause I'm a froggy french!

[Nickel020]

Re: [ GA-EP45-DS4 ] Memory & MCH problems

Decreasing the MCH Core improves stabililty? That's a good find, it point's towards the MCH getting too hot, less voltage = less heat. Your MCH heatsink might not be seated properly, the ebst thing to do is remove it, clean off the thermal pad and apply some thermal paste.
Be aware though that this may void warranty. I asked Gigabyte Germany though once about this and the offcial answer was that it's no problem to do that, as long you don't mechnanically damage something. Other countries Gigabyte offices might handle this differently though.

[FragassRock]

Re: [ GA-EP45-DS4 ] Memory & MCH problems

That is exactly what I have feared! Is the heatsink on the northbrige easy to remove ?

[Nickel020]

Re: [ GA-EP45-DS4 ] Memory & MCH problems

You need to remove the mainboard first. The heatsink is fastened by little push pins that you need to "contract" (for the lack of a better word) at the backside of the motherboard to push them through the motherboard and remove the heatsink. Small pliers might be useful for this.

[FragassRock]

Re: [ GA-EP45-DS4 ] Memory & MCH problems

And isn't the heatsink somewhat glued (with adhesive thermal paste) over the the NB ? Is it hard to remove ?

If I use not adhesive thermal compound (like artic silver 5) and the heatsink fastened by the original little push pins is it problematic ?

[Nickel020]

Re: [ GA-EP45-DS4 ] Memory & MCH problems

It's a thermal pad, and the problem which is kind of sticky at first but is not really thermal adhesive. People often accidentally push the NB heatsink when isntalling CPU coolers causing the heatsink to become a little lose permanently and causing temps to become worse. This happened to me as well.
I don't know why Gigabyte doesn't use better thermal pads...

[FragassRock]

[Solved][ GA-EP45-DS4 ] Memory & MCH problems

Thank you Nickel020 it work!

The heatsinks with heatpipes were in fact very simple to remove. And then I saw what kind of thermal cement were used on the northbridge... It 's such a shame that GigaByte use such material.

So I removed everything and put some of that good old Arctic Silver 5, then i put every thing in place. It seems to me that the AS5 is even more adhesive that the previous thermal thing...

In the Bios I set every params of MIB to [auto] wich didn't work before and then passed 2 OCCT RAM test of 30min in a row (case opened, case closed) with no problem! That never happened before with those settings!

When I touch the NB heatsink it now get hotter than before which indicate better thermal performance.

Thanks again Nickel020!