x6800 + asus p5wdh + ln2 problems - 4.9 ghz wall

[Delex]

hi,

we are testing x6800 + asus p5wdh (vcore vmch vdimm mod) with ln2 but we're experiencing some problems: we reached 4.9 ghz (380x13 - about 400x12) but after that it crashed.
The BIOS we used is 1407 (the 1707 and the 1801 ones blocked the multiplier).
The CPU is a step 6-b2, the RAM instead is a cellshock 1000c4.
The maximum temerature we reached was -135.


Where is the problem?

Thanks

bye

[blind_ripper]

max fsb ?

[TaPaKaH]

X6800 @ 4.9GHz is already very nice :toast:

I see a couple of reasons:
1)Bad CPU
2)not enough Vcore
3)BIOS issues

[Delex]

with an other x6800 the fsb wall was at about 460 mhz...we tried 400x12 wtih this 6-b2 x6800 and working. But over 380x13 don't working...why?:(

[ojdr2001]

Try BIOS 1601

What voltages did u used?

Found CB at what temp?

[Delex]

X6800 @ 4.9GHz is already very nice :toast:


No...not good :P uder dry ice this cpu working at 4.7GHZ :stick:


I see a couple of reasons:
1)Bad CPU
2)not enough Vcore
3)BIOS issues

Vcore..1.93 maximum :P

Why? :slapass: :slapass:

[Delex]

Try BIOS 1601

What voltages did u used?

Found CB at what temp?

We will try today...

Voltages: from 1.80 to 1.93

CB at about -135°C...but I think that the max temp depends from insulation of mosfets and other components...much noprene...much temps :)

BYe

[majkel84]

4,9 is a lot

you must have real nice piece of silicon to do over 5G :-)

I assume that it's the CPU issue

Voltage increasing dosn' help ?

[cpu4you]

Wow, would like to see 5.0ghz and what you did to reach it. Definitely be watching you.
joe

[prosk8]

Hammm 1.your Stepping No So Good To Oc The Best Is B1 5
2.more Vcore
3. The Bios
4.try More X6800
5.maybe The Mobo Not The Best
6.the Hd
And I Have More

[Drag]

Maybe your hd asks to much from your cpu?

[oysfaerg]

I would have tried disabling one of the two cores whether to see if one of the cores won't go past 4.9GHz or of both of them alone won't go past 4.9... If one of them crashes at 4.9, but the other maybe stops at 5-5.1 you have the problem right there...

[Delex]

Hi,
thanks to all ;)

The hard disk? WHY? Btw...the HD is a maxtor diamondmax 10 200 gb sata. We were used this HD with a p5b deluxe and asus p5wdh (X6800 5-b1 ES) and at 4.8 Ghz crush....:slapass:

[SLi_dog]

Since no-one else has suggested it, maybe RAM problems?

Have you tried reducing tRD and tRFC?

Or........try reducing the FSB and increasing the multi? Maybe try 340x15. That's what I used to get 5.1Ghz with only 1.74vCore.