Overclocking an M0 Xeon

fishfishfish · 13 Nov 2008 at 19:21

I've been fiddling around with my old rig this evening. It's based around an Asus PCH-DL motherboard, a pair of 2.4GHz M0 stepping Prestonia Xeons and 2GB of RAM, wrapped up in a Lian Li PC 6070 case. I'd never tried overclocking it before (my new Q9550 was my first ever overclock) and I've been surprised quite how easy it is. I've just got an 18% overclock, taking it up to 2.8GHz, without really trying, and it's OCCT stable after an hour.

I don't know much about this board, but the FSB goes up to 165 and the multiplier only goes to 18, so I am guessing I'm near the limits of its capabilities already.

Does anybody have any experience of 'clocking these, from back in the day?

Thanh55 · 13 Nov 2008 at 22:57

With my tiny knowleage, Intel never have Xeon overclock board except Skulltrail (5400 chipset). You could try Clockgen but I am not realy sure.

PhillyDee · 13 Nov 2008 at 23:09

Pretty sure these needed some sort of voltage mod too or something similar. I had the exact same board . . . . Bought from someone on here.

fishfishfish · 14 Nov 2008 at 09:07

Excellent. Thanks.

Looking into it, the PCH-DL doesn't seem to be quite as good for overclocking as the PC-DL or NCCH-DL.

Apparently the standard settings on the PCH-DL allow you too have a CPU Clock from 133 to 165, with a multiplier of 12 to 23. The latter depends on the processor installed, and my M0 Xeon allows only a 12 to 18 multiplier.

However, there's something called the "moose mod" mentioned for the PC-DL, which involves moving the FSB jumper to the top two right most pins.

This is the default "CPU select" setting, which goes to 133-165 on my 2.4 Xeon.

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--
..

This one gives 100-133.

..
--
--

This gives 166-200, leaving a jumper spare.

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Unfortunately, setting it to 12 x 200 (2.4GHz) makes it a bit unstable though, and it's only posting intermittently. The speed is also being detected as 166x12 1.88GHz. I upped the Vcore from 1.6 to 1.7 to see if that made any difference. It then shows the speed as 1.2GHz.

This gives me 200-233, leaving a jumper spare.

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Setting this to 12x200 at least posts again and reports correctly as 2.4GHz, which seems promising. I'll give it a go and see how it fares.

fishfishfish · 14 Nov 2008 at 13:22

Ah, this is fun.

I've applied the Moose Mod and have set the FSB to 200 and the multiplier to 16 (3.2GHz), which gives me an overclock of about 34% on the CPU. It gave me an Vcore error after 10 minutes of OCCT. So I've tried increasing the volts from 1.6V (bios) to 1.7. However, this still shows up as 1.46V in Everest.

It could do with better cooling. I'm using a Lian Li PC 6070 which isn't great in this respect - it's designed to be silent. There are only three 80mm fans and no ports to fit additional fans.

I tried attaching a massive 120mm Panaflo fan out of an old SGI 540 to the case using Gaffer tape. This was working well, and shaved several degrees of the temps, but then I made the mistake of catching my thumb on it. Resulting in a blade snapping off, and a hole in my thumb. The fan is now too wobbly to use...

The temps rose from 31 idle to 51C after 20 minutes of Prime - at which point the fans went from 4000 to 5500rpm. I've had a couple of errors at 213x15 and 200x16, so then tried 210x15 (3.15GHz). I'm guessing that it's the voltage that's preventing me from going higher - Windows seems to suggest I'm still on stock volts. Apparently these chips will do 3.4-3.6 with ease.

PhillyDee · 14 Nov 2008 at 14:25

Google this
pch-dl xeon volt mod
comes up with quite a few overclocking tips for the board and the cpu's.

Problem in the sockets are so close to each other that you cant get a better hsf on there. I discovered that the stock intel fans were incredibly noisy. Though good cooling. Swapped it for some ambers to find the cooling wasnt as good, but I preferred the silence tbh.

fishfishfish · 14 Nov 2008 at 16:07

Thanks, PhillyDee. I've just been reading up on that. I think that sort of mod might be beyond my capabilities, so I think I'll just stick to running them at stock volts. The 3.15GHz overclock I did earlier is has been priming for a couple of hours and all looks good. The temps have also calmed down a bit - they're now maxing out at 43C on the IWT fans.

The whole machine is a tad on the noisy side, thanks to the PSU, and I've got several other noisy machines on my desk so I don't really notice it that much, until I turn off some of the others.

This one is just a toy. Might try and turn it into a Hackintosh perhaps.