MSI K7N2 Vcore problem...

[smok3yjoe]

Help! I've reached the limit for my box, and can't get any further...

The box Prime's at 198Mhz (54.C full load & stock Vcore), but 199Mhz produces rounding errors whatever happens to the RAM timings, so... I upped the vcore by 0.025V and dropped the FSB 10Mhz to compensate for the extra heat, just in case. Now, when the box Prime's, it locks up!?

The temp seems a little peaky, but never seems to break 55.C.

I'm a little perplexed. It's not an issue with running higher Vcore (I guessed at a duff bios), as at stock FSB (my multi is locked), the box will happily run higher Vcore's. I've tried flashing the bios, upgrading the PSU, adding cooling to the RAM, slackening timings, single and dual channel mode, increasing & decreasing Vdimm (these chips report 2.5V as stock voltage?)... nothing works...

Also, running the RAM Async at 200Mhz, FSB 166Mhz, causes prime95 to error. I know async is bad for o/c'ing but is it also dodgy for stock CPU Mhz? Is my RAM causing this problem?

I'm currently thinking that it might be a heat disspation issue (sudden increase in temp causes lock up before mbm5 monitoring picks it up???), but I kind of feel I'm grasping at straws...

This is my first O/C and am hoping I've missed somethign simple...

Any ideas from those who know a little better than I?

As an aside, I heard something about the Vdimm control on these boards and wondered if anyone knows about it? Apparently, the Vdimm setting in the bios also controls the northbridge voltage? I have heard that some boards allow you to control these independantly, and that you can get a bios for this board that has been hacked to allow you to do this. Try as I might, I can't find any reference to it on the web - agian, any ideas?

[SteveI]

I don't know your mobo, so I don't know if I can help...
Does it have on board GF4? If it does, your max fsb and memory speed may be limited to under 200mhz.

If not, it could be your memory. Running asynch will hurt performance, but should not cause instability by itself. Are you running a locked barton 2500+? If yes, when you ran memory asynch to 200mhz, did you bump vdimm? Even PC3200 often needs extra voltage to run stable.

Regarding the vdimm also controling NB voltage, I don't think so. Usually, this is wishful thinking. I hope I am wrong tho. On a non IGP mobo, you should not need to bump NB voltage to run 200mhz. Also, with a locked barton, running 2.2ghz should not be a problem. It sounds like you may have gotten a real lemon.

BTW, If memory serves me correctly, the volcano 9 is a real dog. If it has a variable fan, crank that up as fast as it can go... See if this improves stability.

Good luck with it.

[smok3yjoe]

thanks for coming back to me....

I'm not familiar with the term GF4? I'm assuming you refer to on-board graphics? If so I've only got a 32Mb Radeon in there, but I'm not a gamer (I'm a server tech by trade and can't bring myself to put the time in for games!) so I wasn't too concerned about it. The box is mainly used for video encoding work.

This mobo has the NForce2Ultra chipset, so I'm hoping 200Mhz should be ok? I've seen these boards reported at running 220Mhz FSB with stock Northbridge cooling, apparently higher freq's need upgraded cooling (240 is allegedly possible), but the temps on the NB only get to around 35.C at the mo. Is this too high?

I've tried upping the Vdimm, but this seems to have little effect on the stability, however, the board will only allow as far as 2.7V. I've just seen a modded bios that allows 2.8, so I'll give that a whirl soon.

sorry to be dim, but whats IGP?

As for the quality of the volcano9, I think you're right. however, it does come with a 74CFM fan (the worlds noisiest I think) which is cranked all the way up. On the subject of replacing the heatsink, I'm a bit limited as this mobo doesn't have the four holes around the socket. This obviously precludes the thermalright sp's that everybody raves about, do you have any recommendations? I've heard that the Aerocool DeepImpact range are good, do you have any thoughts on them?

One last question... Is ti worth fitting any sort of Southbridge cooling? there's none as standard and I run SCSI drives off an adaptec 39160, which I assume will load the southbridge more than is usual?

Sorry to come back with so many questions, but thanks again for your help!

[danrok]

It would be well worth updating the BIOS to give you that 2.8v option on memory. It might help, there's only one way to find out.

My XP3000 is the 166Mhz version, but it will run at 200Mhz and higher.

Try to get your CPU and memory running in sync at 200Mhz or so.

The stock NB cooling should be OK if you haven't increased the NB voltage. You probably won't need to increase NB voltage unless you have IGP.

IGP = Integrated Graphics Processor, i.e. graphics are built in to the NB chip.

The SB should be OK without cooling, it runs fairly cool anyhow.

Also, ensure all you fans and filters are free from dust to give best possible cooling.

[danrok]

As far as cooling you CPU goes, without mounting holes on the mobo, a large aluminium cooler with a copper base is ideal.

These akasa's are very good http://www.overclockers.co.uk/acatal...Akasa_119.html

Don't be put of by the low price - they are good quality.

[smok3yjoe]

I've made small progress, but progress none the less!

The box has now primed at 201 for 15 mins, so I guess that's a little more like it. I eat my words about the vdimm not helping, it was necessary to up it to 2.7V to get stability. I've got the new bios in, but haven't really had time to play around with the ram at 2.8V; I set it once, it locked up, so I've gone back to 2.7V for now.

The wierd part is that hard setting the Vcore to 1.65V in the bios instead of letting the bios use the bridges seems to help stability? Makes no sense to me.

It would also appear that I was having air flow issues. I have two 92mm front intakes, two 80mm exhaust, and had one 92mm side panel intake. Removing the side panel intake and reducing the rpm on the intake fans seemed to drop cpu temps by 3.C.

As for cpu cooling, I have decided to try a custom solution. A friend of mine is well versed in the workings of fridges, and reckons we can create a compressor based cooler from a scrapped fridge. Apparently it should pull the cooling plate down to about -6.C, so that should help a bit!

anyhoo, thanks for all your help!

[SteveI]

You don't need the 4 holes to use a thermalright. 3 of my Thermalrights don't use bolts, SK6+, SK7, SLK900a. The 900a is probably about as good as it gets while still using clips. Better cooling on your CPU is probably in order.

On my NF2 mobos, 52-53 seems to be the upper limit before I start getting stability issues.

[smok3yjoe]

Thanks SteveI. The temps coincide with what I'm seeing, so that's reassuring. I had believed that the temp would go much higher before it caused any problems, but I guess I'm still learning...

good call on the thermalright slk900a. I'd not spotted that before, and will be putting my order in tomorrow for one (pay day! ).

BTW... if anybody else is looking for this heatsink in the UK, Chillblast are a bit cheaper and have it in stock. The only two stockists i could find were Overclock and Chillblast, Overclock were are out of stock and keep changing the expected date.

http://www.chillblast.com/customer/p...?productid=246

[smok3yjoe]

Just thought I'd come back and say thanks for the advice. Am now making slow progress, things are alittle strange at the mo, but improving...

Got the SLK900a, finally got a reasonable fan on it and things are good.Temp never seems to get above 45.c, and I'm able to give the chip a little more voltage. I'm hoping the Vantec Tornado will help further.

Bizarrely, the RAM seems to be running best at 2.5V now?? I'm still not setting any records, am wondering if it might be worth ditching the proc and trying a mobile? This all seems like flogging a dead horse at the mo...

One last stab in the dark, the vcore seems to vary a fair bit. The board over volts anyway by between .4v and .6v, but the fluctations can get as high as .4v. Am I being over-picky or does this seem a lot?