OCing 2.8Ghz to 3.36 locks up and video corruption ?

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ScottFern

Diamond Member
Oct 23, 2002
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that corruption is gone now. I am now in a "testing phase" for the stability right now. I just wanted some input about my bios settings and if they are correct?
 

ScottFern

Diamond Member
Oct 23, 2002
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oh yeah, if you get the right mobo, I prefer the P4C800 or the Abit with the I875 chipset. I just upgraded PSU and RAM too.

It was worth it, it paid off, over 700Mhz gained.

You should be able to easily get to 3Ghz with the right setup.
 

Mullzy

Senior member
Jan 2, 2002
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Originally posted by: PhoenixOrion
At an overclock of 20% to 3.36Ghz, you should not need vcore adjustment.

Assuming that you are using 2.8 "c" northwood chip, these cpu's are very good overclockers that the stability might come from your PC3200 memory. 2.8c perform great on i875 chipset (canterwood) mobo like the p4c800-de.

You didn't mention what brand of memory you are using.

My suggestion is to ditch the AI OC function and set everything manually:
1. set the fsb/mem divider to 5:4 instead of 1:1 with both vcore and vddr at default. at 3.36Ghz, check stability. if not stable then you know your cpu is the bottleneck.

2. if stable after step 1, change divider back to 1:1. then set vddr to 2.8v and "lock" or "fix" the agp/pci frequency. overclock to the 20% by raising fsb to 240. if not stable at this point, then start bumping vcore. default should be 1.52v and keep bumping no higher than 1.62v to avoid premature aging of cpu.

FYI, my 2.8c maxed out at 235FSB (3290Mhz) at 1.65v on an Abit IC7. I can't get it stable at 240FSB even with 1.7v so I backed off. It's possible that my board is undervolting quite a bit but I'm sure that many 2.8c's are not going to get a full 20% overclock.
 

ScottFern

Diamond Member
Oct 23, 2002
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76
I experienced a lock up while I was encoding a dvd. That was at 250fsb*14=3.5Ghz

I took it down to 245fsb*14=3.43Ghz, but I upped the vcore to 1.675v and now it stays right at 1.69-1.71v. I am worried that i took the vcore to high ??

Tonight I think I will run Memtest86 and go from there. Any suggestions ?
 

ScottFern

Diamond Member
Oct 23, 2002
3,629
2
76
I am having all types of problems! I can get into WindowsXP and do my normal stuff, but I can't encode a dvd for any type of OC. Now, I am at 3.36Ghz and it still will lock up and/or reset the computer. I don't understand whats the weak link here :(

HELP? Is it the voltages, cpu, mobo ? mobo bios settings?
 

jiffylube1024

Diamond Member
Feb 17, 2002
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Originally posted by: ScottFern
I am having all types of problems! I can get into WindowsXP and do my normal stuff, but I can't encode a dvd for any type of OC. Now, I am at 3.36Ghz and it still will lock up and/or reset the computer. I don't understand whats the weak link here :(

HELP? Is it the voltages, cpu, mobo ? mobo bios settings?

Running the CPU at 1.7Vcore is not a good idea- that is how P4's die unless you have extreme cooling (ie LN2, Prometia, etc).

That ASUS board overvolts like nuts too, so 1.675V actually can put 1.72V+ through your chip.

If you were on Abit (IC7, it's the other way around - the board undervolts like nuts, and a 1.675V setting is good for 1.62-1.64V; you have to set your voltages lower on ASUS boards.
 

Mullzy

Senior member
Jan 2, 2002
352
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If you have a 2.8c like mine you may only be able to do 235ish FSB no matter how much voltage you throw at it.

You should really get it completely stable much lower than going straight for 250FSB. Back off your voltage to stock (1.525v) and run some Prime95 tests around 220fsb. Then start increasing your FSB 5 at a time until you need more voltage again. With an overvolting ASUS you should get around 220-230fsb without any need for more voltage. After that it's entirely chip dependant.
 

ScottFern

Diamond Member
Oct 23, 2002
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thanks guys that really helped. I am going to try exactly what you said.

on a side note, you are 110% right, its entirely chip dependent, I have the best power supply and ram for OCing...so....I will report back shortly.
 

ScottFern

Diamond Member
Oct 23, 2002
3,629
2
76
For my asus p4c800 mobo whats the best "overclockable cpu" out there ? just curious, everyone was saying, OMG P4 IS THE BESTEST THING EVER TO OC!!!!