Legit Reviews

Hi All,

I'm trying to get my desktop machine stable. It blue screens twice a day currently I contact DFI directly and they said it was because I have the wrong processor for my board so they can't support it. Basically I have the following:

Intel Pentium m760 (133MHz FSB)
DFI 855GME-MGF (CPU-Z reports revision A2)
2x Kingston KVR266X72C25/512

I had this system running perfectly stable for 5 months until I added an extra 512MB RAM. An now it crashes twice a day. I bought a replacement memory stick for the second slot but still have the problem.

I found an option in the bios that lets me increase the MB FSB from 100->133 but then the system won't post. My knowledge doesnt go beyond that as far as tuning the bios.

What I'm looking for is someone who has this board running stable and can give me some bios setting that work. I'm not bothered at this stage to overclock, I just need it stable again.

At first I thought it was the onboard graphics becuase it always crashed while running opengl stuff for more than a few minutes. But I use now a seperate card for graphics.

Thanks to anyone that can help.

Peter

Try running the system with only one memory module, if it crashes, try with the other one, and try all the mem slots of the mobo, maybe you have a broken one

System still seems stable with 1 but unstable with 2 sticks. I read that the frequency mismatch (CPU 133) (Board 100) could be causeing this problem. So if anyone has the proper bios settings I need, that would be great. Otherwise, maybe a good memory diagnostic tool??

yeah definatley was gonna recommend memtest86, priceless peice of software, literally and metaphorically!

But, since you say u replaced the stick it may not be the new memory stick but the old one. It MAY be that when u installed the new one some static may have been discharged into the old one or whatever... i would test each stick indidvidually in different slots.

Keep us posted!

update: after wasting some effort burning knopix to get a bootable memtest86, I came across the fact that the DFI board has memtest86 built into the bios!! great stuff.

So I ran the test with the system untouched. And 3 errors showed up in the >512MB range. So I then systematically tried each of the sticks seperately (including the original suspect module) All three passed 100%. So the I tried a stick in the second slot, also 100% pass. so the memory and slots seems okay, until they are both loaded...

I noticed that memtest86 reported my ram as 177 DDR354. which seems strange since i thought this is DDR266. There was also another sequence of numbers that I've seen posted around here for the timings. 2.5-3-2-6. I dont know if thats good or bad. But I'm starting to believe DFI now that this processor at 533 just isnt going to work on the board which supports max 400mhx FSB (according to them) so what magic am I missing to make this work???

I checked the manual for the board and I have the jumper for the CPU set to 133. If I change the bios from 100 to 133 the system wont post and I have to short out the bios rest jumpers. the ratio is being picked at 4:3 but I read somewhere this might be better at 1:1. I tried to read some stuff on what all these numbers mean, but even though I've been around PC's for a long time as a developer. This is really confusing me.

Any more tips would be welcome. Ive searched and searched the web to find a step-by-step guide to making this work. But this board seems to be the only real source of knowledge. Help?

Thanks

Peter

The problem is, if memtest is reporting properley, that your RAM is being overclocked from its default of 133 to 177. Now thats a hell of an overclock and im impressed it hasnt failed more often.
The ratio is always best to be at 1:1, theres your problem, 4:3 means ur overclocking the memory i think and thats causing ur instability.
Im thinking its cause in one stick operation the stress is lower than in 2 stick operations thus no problems.

But yeah, set the ratio to 1:1, thatl sync FSB and MEM and also increase performance and hopefully stability too!

Well I tried setting it to 1:1 and left the system testing for a full 24hrs. And yippee! it seems stable. No memory errors being reported. But... from the bios I now have:
CPU clock 100MHz (on the mother board I have the jumper set to 133)
Async PCI AGP CLK 33/66
Memory ratio 1:1
Ram Freq. 100MHz
PCI Freq. 33MHz
CPU Freq. 1500MHz

FID/VID disabled (FID 15x VID 1.34)

Ram in memtest is reporting as ddr200! so it seems now like I'm underclocking the system But if I try to increase the first value (CPU clock to 133 the system wont even post) ANy other tips. At worst I'll just run it like this and save some power ;)

Cheers

Peter

PS and thanks for your help so far!

Sorry to post late, but just wanted to confirm what you guys already stated. You are running Kingston ValueRam that is rated at DDR266 at DDR354, which is a very high overclock for those modules on a board with no memory voltage options. Since you are getting memory errors and instability the solution as already noted would be to put the memory divider down to 1:1 or invest in some new memory!

Happy 4th

You are under clocking your system there by the looks of it now.

The FSB should be at 133Mhz for that processor. Have you inadvertently changed a BIOS setting to 100Mhz instead of 133Mhz?

Dan

I've listed my current bios setting a few posts up, but as mentioned, if I change the CPU to 133 the system wont post. Could this be some issue with the jumper on the mboard (CPU FSB Select)?? I disconnected it to give me 133MHz as the manual suggestes.

Cheers

Peter

Does it still refuse to POST at 133mhz FSB after you changed the mem divider to 1:1?

Dan

The motherboard is set to 133 (jumper removed)
And the first bios setting is 100MHz, if I change that also to 133 it wont post.
That's with all the other settings as I mentioned above (inc 1:1 mem ratio) Strange eh?

are you sure the CPU is a 133Mhz part... the only reason a working system wont boot is if the CPU is too overclocked, or one of the funmanetal buses is overclocked, so either a divider somewhere is set wrong, or the CPU isnt a 133mhz part.

From what Ive seen it confirms that you have a 760 rather than a 755, but can you just double check please.

OK, this is everything that I can think of that might be the problem, it may take a while to check everything, but hopefully something here will help fix your problem.

For the PCI/AGP setting is that set to FIX: 33/66, because it should be.

Im wondering if the FID/VID is the cause of the non-POSTing so try enabling the FID/VID and setting them to the maximum available (I thnk they are already but just need enabling) and see if that will boost your CPU past 1.5Ghz. It may be that you need to enable the full speed and voltage to run the CPU at 133Mhz FSB

Try increasing the BIOS CPU setting from 100 to as high as you can in 5mhz jumps, and see if it POST's or not. Tell us what you get to before it 'dies' on you (Or stop at 133Mhz if for some unknown reason it works this time).

If you definatly have a 760, and the board wont get much past 100Mhz (though review sites have overclocked your board's FSB to as much as 175Mhz, which is strange as to why your board wont get to 133Mhz), then something must be wrong that I cant think of off hand.

If none of this doesnt help, disable the FID/VID and change back your RAM:FSB divider to 4:3 to at least run your RAM at its proper speed.

Dan

CPU-Z screenies:

http://www.whitehexagon.com/cpu-z1.png
http://www.whitehexagon.com/cpu-z2.png
http://www.whitehexagon.com/cpu-z3.png
http://www.whitehexagon.com/cpu-z4.png
http://www.whitehexagon.com/cpu-z5.png
http://www.whitehexagon.com/cpu-z5b.png

I'm going to try some of the suggestions at the weekend, right now I need to do some work on the machine while it's stable

Cheers

Peter

and the bios page

http://www.whitehexagon.com/DSC05333.JPG

When did you take those screenshots? Because according to CPU-Z, everything is running as it should be, i.e. 533Mhz FSB. Yet the BIOS shows that its slower than it should be

Dan

They are all the current system settings. I'm wondering if its something to do with the jumper on the MB I mentioed. Maybe I need to set that to 100, and then the bios to 133. Maybe together they are clashing. I shall try that also at the weekend.

Well as it is there's nothing wrong with how your computer is running.

I think maybe the 'problem' is that the BIOS doesnt know about the jumper settings. So that the BIOS thinks that the CPU (FSB) clock is at 100Mhz, when because of the jumper its actually at 133Mhz, so when you set the BIOS to 133Mhz as well, it boosts the clock by 33Mhz, which actually makes it run at 166Mhz. This would probably explain why it isnt posting, as the CPU probably cant handle an overclock to 2490Mhz (At least not without some extra voltage, which the MB cant supply).

Well thats my take on it anyway. So there is no real need to alter anything, unless you want to try and change the jumper back to 100Mhz and see if it works normal when changing the BIOS to 133Mhz.

Dan