Jimbo_J wrote on 2024-01-26, 20:35:

Hello all,

Please can anyone tell me if it is possible to override the motherboard processor clock multipliers (the jumper ones) via the bios? I understand, from the manual, that the P6DBU is limited to 8.0 as the maximum multiplier via the jumpers. It is possible to use over an 800MZH slot 1 or socket 370 processor (via a slotket adpator ) on this board?

Thanks

Welcome to Vogons 😀

Once you're using multiplier-hardwired coppermine processors, those jumpers are pretty meaningless. Supermicro do have a table up to x9.5 (attached) but again its not relevant to coppermines.

I've run my P6DBU with both slot 1 & sloketed 370s without issue - the board will even run 133MHz versions though at a lower overall speed (unless you tweak the fsb in the BIOS)

Probably best to make sure you're running the latest BIOS (attached)

Thanks for this I really appreciate the help. The board is a rev 2/3 one with 5 PCI slots and the bios currently on the board is 3.1. The board will post with 2x SL2U7 P2 450 CPUs so I know the board is working. I tried the 2x SL43F P3 850 CPUs on the 8.5 jumper setting (even though as you mention it shouldn't affect the CPUs) and they just would not post. I will try again later once I've updated the bios version you've shared though I'm starting to think that the p3 850 CPUs are just dead.

Jimbo_J wrote on 2024-01-27, 16:30:

Thanks for this I really appreciate the help. The board is a rev 2/3 one with 5 PCI slots and the bios currently on the board is 3.1. The board will post with 2x SL2U7 P2 450 CPUs so I know the board is working. I tried the 2x SL43F P3 850 CPUs on the 8.5 jumper setting (even though as you mention it shouldn't affect the CPUs) and they just would not post. I will try again later once I've updated the bios version you've shared though I'm starting to think that the p3 850 CPUs are just dead.

I've re-checked in case I was misremembering the boards cpu support, but my P6DBU (rev 1.1) definitely supports coppermines. Here's some pics of that check with latest BIOS at both 100MHz (AUTO / default) & 133MHz (BIOS OC) fsb x 7.5...

Another thing to check is the cpu VRM chips on the board. At some point after release, Supmrmicro switched the VRM chips from Harris HIP6004ACB to either HIP6004BCB (what mine has) or HIP6004CB - only the last two support Coppermine voltages, though for some reason Supermicro claim that this switch didn't occur until rev 2.xx PCBs. The chips to check are marked in this last pic.

Ahh now that last bit is probably the issue. My board has the Harris HIP6004ACB VRM chips. I'm guessing that that means no Coppermine CPUs and I'll be limited to Katmai SL3JT or SL3JM CPUs. Would you know if one of the higher end slotket adapters that lets you select the voltage would possibly work? I'd prefer to keep the SM motherboard but also would like to run XP. Thanks

Also wondering if the Harris HIP6004ACB chips could be swapped out and replaced with HIP6004BCB chips by any decent PC repairs company??

Jimbo_J wrote on 2024-02-03, 13:39:

Ahh now that last bit is probably the issue. My board has the Harris HIP6004ACB VRM chips. I'm guessing that that means no Coppermine CPUs and I'll be limited to Katmai SL3JT or SL3JM CPUs. Would you know if one of the higher end slotket adapters that lets you select the voltage would possibly work? I'd prefer to keep the SM motherboard but also would like to run XP. Thanks

Would probably depend on the slotket - ones that provided their own voltages, like PowerLeap, should be fine whereas ones which have voltage setting jumpers only will still rely on the HIP6004ACB to supply the requested voltage which, in its case, can't be less than 1.8V (this is more than default coppermine voltages but may still work). Also bear in mind that working with dual slotkets (if used) can add further issues depending on the brand / model - do you have any to hand?

Jimbo_J wrote on 2024-02-03, 16:56:

Also wondering if the Harris HIP6004ACB chips could be swapped out and replaced with HIP6004BCB chips by any decent PC repairs company??

Swapping out ACBs for BCBs is not an uncommon mod on a number of boards (think SM did exactly this back in the day - check the foot of this link https://web.archive.org/web/20001211042600/ht … s/Processor.htm ) and should be fairly straightforward assuming no associated caps or resistors need changed as well.