Overclocked p3866 and voltage issues

[Cruze8]

Hi all I have a p3 866 cBo stepping on an asus cuv4x mobo with 256mb of micron pc133 sdram with a hercules gf2gts and a sb live value a 3com etherlink xl net card and a quantum fireball lm 7200 drive now I want to overclock this sucker but I'm having extremely hard time with it.. seems I can never get her stable over 133mhz bus speed... I've tried takin everything but the ram and vid card out... no dice I tried moving pci cards to other slots tried changing vcores.... I've tried running the fsb at 155 with a 1.90 vcore and I get temps of 47c under load.... but it isnt stable... nothing in any combo seems stable over the stock fsb of 133... if you can share some vcore secrets or tell me what I'm doin wrong here I'd appreciate it... also I run windows ME... oh and my lockups only occur in 3d games... I never have problems in windows or running seti@home at high fsb's.. thanks for any help

 

[jkersenbr]

4 thoughts:

1) Maybe your chip just doesn't want to overclock. They all don't. With that being said, most 866's are good for 1009. But 155 is a big FSB step, try to get it stable at 145-150 first. Your temps are good, but I wouldn't give it more than 1.9v. I think your CPU is the least likely bottleneck in this instance.

2) 150MHz+ takes a stable mobo. You're probably going to need active northbridge cooling. A little heatsink on the clock generator doesn't hurt either. Made a big difference on the P3V4X. I never tried it on a CUV4X.

3) 150MHz FSB also takes good memory. 155MHz takes darn good memory. Micron is good, but it's not all that good. If you're going to try 155, you're going to need to get memory intended to do so. Like Kingmax, Corsair, or Mushkin PC150. Standard PC133 is likely only going to be good to 146 or so. Anything more is luck. Mosel and Infineon chips on PC133 are best bets for overclocking past 150 without buying PC150 memory.

4) What powersupply you got? The crashiness while gaming makes me think of this. Your GTS is going to take a lot of juice while gaming, and your powersupply might not be up to the task. It might be letting the voltage drop a little under strain. Install Motherboard Monitor and keep an eye on voltages while trying to make it crash. If you see them dip right as is crashes, blame your powersupply. The Asus Via ApolloPro133 boards are pretty sensative to high-voltage demand video cards anyway.

Best of luck to ya!

 

[Cruze8]

jkersenbr I have a heatsink on the northbridge... I should add a fan is what your saying right??? but I have a 120mm fan blowing cool air over the northbridge also what is the clock generator and whereabouts would I find this????.... so this is mostly a memory thing you think eh??? cuz I have her stable at 144fsb and about my ps... I have 2 120mm fans a 92mm fan 2 hd's 2cdroms plus my vid card and my 2 pci cards..... oh and also I've noticed that my +5 voltages are always below norm aswell as my -5's and my -12 is around -11 -10 and my ps is only 300watts

 

[jkersenbr]

If you've got a blowhole blowing on the northbridge, you should be OK. It was a little more critical to put a little heatsink/fan on the northbridge on Slot1 boards because it was behind the CPU.

I would seriously consider getting better memory.

But your powersupply is suspect. 300 watts is plenty, but if all your voltages are low, then that may be the problem. You're turning a lot of fans -- that's where most of the power must be going. The rule of thumb is the 5v lines need to be within 5% and the others within 10%. So if your 5v is dropping to or below 4.75, I'd recommend a better powersupply (not necessarily bigger, but a brand name like enermax, PCPower&Cooling, Antec, ect) or putting the fans on a separate powersupply from the mobo and drives.

 

[Cruze8]

ya it is a blowhole right over the northbridge..... and about the ram is there really pc150 sdram??? cuz I've never seen that... if so where could I get some of that... I'd need 256megs in a single stick... also I'm in canada so I'd need it for as cheap as I could get it.... ya my 5v lines are always pretty low... even idling they are at 4.893 so you recommend a new ps and ram???

 

[jkersenbr]

RAM is where I'd start. Sure there is PC150. Even some marketed as PC166 (but it's not any better than PC150). The best, IMHO, is Kingmax with the TinyBGA chips. I never had any that wouldn't run CAS2 as fast as my mobo could go stable, and I always ran 2x128MB sticks. See Here. I'd try putting a Wanted to Buy add in the For Sale/Trade forum first though. You can probably get it cheaper there than from a store. You can always do a search at Pricewatch too.

If that doesn't fix it, then I'd try a 2 powersupplies. An AT (not ATX) powersupply for the case fans and your current powersupply for the mobo and drives. I think taking some of the fan load off would fix the problem. If you don't want to mod up 2 powersupplies, then your best bet is a new one.

 

[Cruze8]

well thanks for all your help man.... I got her stable at 144fsb but that aint enuf for me... I'll take a look into the ram... but I dunno if it is the ps... I couldnt overclock before I put my case fans in and added the second hard drive..... oh and by the way man what vcore would you suggest for 1007mhz???? up from 866??? default vcore is 1.65

 

[Cruze8]

oh and it says that the ram is 168 pin... will that fit into my asus cuv4x???

 

[jkersenbr]

168 pins....of course it will work with your CUV4X. It's a regular SDRAM DIMM. It'll work.

1.9v is really the max I'd play with on your chip with any overclock. It really shouldn't need more than 1.8v to do 1007 though. If your memory fixes the instability, back off the voltage and run the minimum possible that is still stable. This will keep your temps as low as possible and will keep the life of your chip as high as possible.