Overclocking for dummies?

[Psyclone]

First my system specs:

Abit BX6 R2 using latest BIOS
Celeron 400 Retail
64MB Mushkin PC100 ECC SDRAM Rated @ 125Mhz w/speed eeprom
20 Gig Maxtor DMA 66 drive hooked to the onboard DMA 33 controller running as primary master
2 2.5 gig HD's secondary master and slave
Pioneer 32x SCSI CD Rom hooked to Adaptec 2940
Phillips 2x Burner hooked to Adaptec 2940
TNT AGP 16MB
SBlive PCI
Adaptec 2940 PCI SCSI Adapter
Linksys Etherfast 10/100 PCI NIC
Brooktree based capture board(currently disabled)
Ne2000 ISA NIC(For ICS)
Creative Voodoo2 12 MB PCI

All,

My Celeron 400 is getting tired. When I bought it, I bought an Abit BX6 R2 board to go with it. I had intentions of having lots of option on overclocking this bad boy. Well being an idiot about overclocking, I didn't know the multiplier was 6x on the chip, this left me with few options when the overclocking part came. I have been running at it's 400mhz since I bought the thing. I am getting a PIII or PIV machine at the beginning of the year so I am not dropping any $$ into this machine. Way back when this chip was new I did a bit of reading here and other forums and saw that people were pretty easily ocing these to 500, some beyond that had fancier FSB options. I tried myself doing 100Mhz FSB yielding 600Mhz, of course it didn't boot. I messed around with the settings, and not knowing as much then as I do now gave up the idea of overclocking the chip.

So last night I decided would be a good night to see what I could get out of it. So I set my FSB to 83 Mhz, yielding 500 at the CPU. I turned it on and hung in pre windows boot several times. I set the AGP/CPU clock to 2/3, and was able to make it into windows before it locked. I set the CAS, RAS junk, whatever that means to 3, 3, and Auto. Still no boot. I turned ECC on, still no boot. The only way I could get it to boot was to set the FSB to 75Mhz, which only gives me 450 at the CPU. So knowing that my memory can handle the paltry 83 Mhz, and an educated guess says the CPU should be able to handle 500 Mhz, what other things can I suspect as preventing me from hitting the 500 mark??

Thanks for any help,

-Psyclone

 

[Dexion]

well.. before we start analyzing the CPU, what kind of cooling or you using? What kind of heatsink? Any thermal compound?

 

[celery550]

I ran a celeron 400 @ 500 for 9months, I recall I had to up the voltage to get it stable at 83FSb

 

[KR]

Try disabling the UDMA selection in the bios and/or disable DMA in the system properties. Often the older hard drives will not handle the PCI/IDE overclock. Also, as was suggested, a voltage bump to 2.1 - 2.3V for overclocking is not unusual.

 

[Neoplasia]

FWIW, I have (well had sort of, left this computer at home for my parents) a celeron 400 ppga on an adapter, MSI 6163 board and some HSF I've never heard of before. 400@500, default voltage, the temp gets up to 33C or 34C under long heavy loads. Tried for 100FSB but I not even POST.

 

[Dark4ng3l]

I can help up the damn voltage and it will work. I think 2.1 - 2.2 is safe.

 

[Psyclone]

Thanks for all your input guys. I had thought about the voltage thing but not knowing whether I should up it or lower it I left it alone. It defaults to 2.00 for the 400(66) setting. I'll try upping it. Also, I don't think it's my DMA drive, it's a new drive(less than a year old), it's running on a DMA cable as well so all is good there, or at least seems to be. To answer the cooling question, I have no extra cooling, just the fan that was on the chip when I got it, no thermal grease, unless it was added at the factory. BTW my temp reading at 450 is, if memory serves me correct 38C or ~100F. That's from the thermistor tucked into the chip fan housing, the case temp is 116F, didn't look at the celsius reading. That sounds hot to me but I wonder if it's somewhat normal with all the junk I have in that case. What do you all think?

 

[Psyclone]

All,

Well I tried the voltage selection and had 0 success. The default voltage for a Celeron 400 is 2.00. I set it to settings both above and below the default. When I set it to 1.95, the machine didn't get past initialization of the SCSI Adapter. When I set it to 2.10, it bluescreened in some vxd before it got to Windows. When I set it to 2.05, it hung just before going into Windows. I am at a loss as to what to do next, any possibility that one of my pci devices is having a problem handling the bus speed and causing these behaviors? Any other things I can try?

:disgust:

Thanks,

-Psyclone

 

[kponds]

what I would suggest (assuming you have decent cooling is go to 2.2 to 2.3 volts. Your certainly not going to ry the CPU in a short time. Also, I believe your board has a bios setting called something like " speed error hold". If this is enable, it will cause problems when running the CPU out of spec (overclocking) - disable it.

With the voltage at the 2.2 to 2.3 volt level, try for 100 Mhz FSB and if you get a lockup, work your way down (95 Mhz, 90 Mhz, etc) until you reach a point of stability. You may have to reset your CMOS if you crash hard but more than likely you'll be OK. If you reach stability with the 2.2 to 2.3 volts setting, starting backing down the voltage in .05 volt increments until you develop problems, then raise it back up slightly. If you like what you see, and need the 2.2 to 2.3 volts for stability get you a good cooler and good grease for the long term.

One than likely you will need the 2.2 to 2.3 volts. The first CU I ever overclocked was a C400 at 600 Mhz and I did it with 2.2 volts on a relatively large $6 cooler bought at a cmputer show. Did it about 1.5 yrs ago. I used it about 6 months, my daughter used it about six months, and we ultimately sold it to a friend who is still running it.

 

[Dark4ng3l]

actualy that setting is "speed hold error" but was close enuf

 

[Psyclone]

Well, I've tried all the settings that were suggested here and still can't make it to Windows @500 Mhz. I suspect it's my PCI clock divider that's causing the problem, though I could be wrong. The reason I am suspicious is because it seems that when my machine is initializing my burner and cd-rom, it's when the machine stops booting. Also the lights on the drives seem to want to initialize twice which is abnormal, the lights flash on the cd-rom first then flash on the burner, but never go solid, they flash again, then the machine stops. I read that the BX chipset supports a 1/4 divider for the PCI clock but I don't see a setting for it anywhere. I am also not sure what the default divider is for this MOBO. I suspect it's 1/2 or closest to 33mhz as it can achieve depending on the FSB setting. With an FSB of 83 Mhz, I am guessing my PCI bus is running at 41.5 Mhz, and the SCSI card can't deal with it, which is a problem since I need my SCSI card to run the burner and CD-ROM. Any more suggestions or am I screwed?

-Psyclone

 

[Psyclone]

And I also have another question, what does the SEL66/100# setting do in the CPU Soft Menu?? And does it have an effect on booting successfully or not?

Thanks...

-Psyclone