C566 FCPGA won't overclock. What gives?

I bought one of those so called 'pretested' Celeron 566 FCPGA which the seller claimed it can run at 850/100, but I can't get that speed at my system. I tried to yank up the v-core to 1.8v and still no go. I can only clock it at 708/83, and that runs fine at 1.5v v-core. What gives? Anyone else have same experience? Help please.

Will a better HSF help?

If it matters at all, here's the list of all my hardware.
Hardware:
C566 FCPGA
Asus CUBX
Enlight 7237
Micron 128 Cas2 SDRAM
Golden Orb
WD Expert 7200rpm 20 Gig
All PCI cards run fine at 41 Mhz PCI bus speed
Soundblaster AWE 64 ISA

Quote:

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Originally posted by panin:
I bought one of those so called 'pretested' Celeron 566 FCPGA which the seller claimed it can run at 850/100, but I can't get that speed at my system. I tried to yank up the v-core to 1.8v and still no go. I can only clock it at 708/83, and that runs fine at 1.5v v-core. What gives? Anyone else have same experience? Help please.

Will a better HSF help?

If it matters at all, here's the list of all my hardware.
Hardware:
C566 FCPGA
Asus CUBX
Enlight 7237
Micron 128 Cas2 SDRAM
Golden Orb
WD Expert 7200rpm 20 Gig
All PCI cards run fine at 41 Mhz PCI bus speed
Soundblaster AWE 64 ISA

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Make sure the Orb is seated well on the CPU and that you are using Thermal Paste. Have you gotten a temperature reading from the CPU at 708?




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"Everyone knows the best bands are affiliated with Satan."

I'm already using thermal paste, although not sure if it's a good one

Asus PC probe gives temp reading which range from 26-29 C.

Quote:

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Originally posted by panin:
I'm already using thermal paste, although not sure if it's a good one

Asus PC probe gives temp reading which range from 26-29 C.

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Hmm.. You say CAS2 RAM.. Is it PC100?




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"Everyone knows the best bands are affiliated with Satan."

PC-100 it is.

BTW, the temp reading above is when the system's running at 708/83.

Quote:

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Originally posted by panin:
PC-100 it is.

BTW, the temp reading above is when the system's running at 708/83.

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Hmm.. I really don't have any other suggestions for you right now. I wish I could help.. Have you tried the CPU on a different board? Or a different CPU on the CUBX?


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"Everyone knows the best bands are affiliated with Satan."

mine does this too on cubx, the same hardware, same temp @ 708 @ 1.5, but no 850 :.(, even @ 1.8!, wont even post!
maybee its something with the board cos sandra says something like max CPU = 800, so maybee nothing past 800 works? that would be good cos that would be fixed by a bios update

Quote:

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Originally posted by scary_jeff:
mine does this too on cubx, the same hardware, same temp @ 708 @ 1.5, but no 850 :.(, even @ 1.8!, wont even post!
maybee its something with the board cos sandra says something like max CPU = 800, so maybee nothing past 800 works? that would be good cos that would be fixed by a bios update

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SCary_Jeff: So umm, what you're trying to say is that we should wait till the next BIOS update??

I'm pretty clueless about this sandra thing, when you say max cpu=800, does this mean, the board won't recognize those 800Mhz CPUs and above?

Quote:

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Originally posted by panin:
SCary_Jeff: So umm, what you're trying to say is that we should wait till the next BIOS update??

I'm pretty clueless about this sandra thing, when you say max cpu=800, does this mean, the board won't recognize those 800Mhz CPUs and above?

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If his board is exhibiting the same behavior as yours, it may be a pretty safe bet that it is the MB. Contact ASUS and ask them what the fastest CPU that can run on your board is.




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"Everyone knows the best bands are affiliated with Satan."

Quote:

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Originally posted by panin:
I bought one of those so called 'pretested' Celeron 566 FCPGA which the seller claimed it can run at 850/100, but I can't get that speed at my system. I tried to yank up the v-core to 1.8v and still no go. I can only clock it at 708/83, and that runs fine at 1.5v v-core. What gives? Anyone else have same experience? Help please.

Will a better HSF help?

If it matters at all, here's the list of all my hardware.
Hardware:
C566 FCPGA
Asus CUBX
Enlight 7237
Micron 128 Cas2 SDRAM
Golden Orb
WD Expert 7200rpm 20 Gig
All PCI cards run fine at 41 Mhz PCI bus speed
Soundblaster AWE 64 ISA

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By clocking the fsb to 83 you're also clocking the ram up proportionately. I had the same problem and figured out it was my ram limiting me.
Switch the ratio from 66:100:33 to 100:100:33 and you SHOULD be able to hit that magic 850.

Quote:

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Originally posted by demc:
By clocking the fsb to 83 you're also clocking the ram up proportionately. I had the same problem and figured out it was my ram limiting me.
Switch the ratio from 66:100:33 to 100:100:33 and you SHOULD be able to hit that magic 850.

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With the PC100 he has, won't it be running at 83Mhz if the FSB is, or does the CUBX allow you to run the RAM and FSB at different speeds?



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"Everyone knows the best bands are affiliated with Satan."

Quote:

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Originally posted by mpitts:

With the PC100 he has, won't it be running at 83Mhz if the FSB is, or does the CUBX allow you to run the RAM and FSB at different speeds?

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Yea, I thought the speed of RAM = speed of FSB. I don't find anywhere in the BIOS where I can adjust the speed of the RAM independently, at least that's what I know. Is it in the timing, and CAS delay??

To hit 850 with my cu-celery 566 I had to up the voltage to 2.1 (may be 2.2, can't remember). I had to buy a decent slotket converter because my previous lame unbranded one could do sod all voltage. I got an Abit SlotKET!!! which can whoop up the voltage to like 2.9 or something ridiculous like that.

If it was pre-tested do you have a guarantee? If so, just get a new one. Not every 566 will do 850, but if it was pre-tested it definitely should, that's why they charged you probably 40% more $$.

same here my 566 wont post at 850Mhz i have an aopen ax64pro via mobo.