[QUOTE=Flatlander;252358]I haven't tried raising BCLK yet.[/QUOTE]And you shouldn't...

I got to do some other things before I bring up yet another 'puter...idea had been to put the sandy bridge side-by-side the AMD 6 core and compare. I'll wait until march....

[QUOTE=Christenson;252401]idea had been to put the sandy bridge side-by-side the AMD 6 core and compare[/QUOTE]Not exactly the same, but gives you some idea: you can compare single-core performance of an [url=http://mersenne-aries.sili.net/throughput.php?scale=1.2795650924844&cpu1=AMD%20Phenom%28tm%29%20II%20X4%20940%20Processor|512|6144&mhz1=3000&cpu2=Intel%28R%29%20Core%28TM%29%20i7-2600K%20CPU%20%40%203.40GHz|256|8192&mhz2=4400]AMD Phenom X4-940 and an i7-2600K[/url] on my site. I don't have any X6 benchmarks, but I don't think they vary too far (comparing single cores) from the X4. Note the i7 is overclocked, but feel free to adjust clockspeeds on either system in the comparison.

I'm not above being a mersenne-airy myself. Therefore, if those other things get done, I think there's a sandy bridge in my future, wondering how hard it would be to set a GTX460 in it and get work out of it, too, probably under Xubuntu 10.10. I'd been hoping for a price break due to the SATA bug, but it looks like not.

[QUOTE=James Heinrich;252404]Not exactly the same, but gives you some idea: you can compare single-core performance of an [URL="http://mersenne-aries.sili.net/throughput.php?scale=1.2795650924844&cpu1=AMD%20Phenom%28tm%29%20II%20X4%20940%20Processor%7C512%7C6144&mhz1=3000&cpu2=Intel%28R%29%20Core%28TM%29%20i7-2600K%20CPU%20%40%203.40GHz%7C256%7C8192&mhz2=4400"]AMD Phenom X4-940 and an i7-2600K[/URL] on my site. I don't have any X6 benchmarks, but I don't think they vary too far (comparing single cores) from the X4. Note the i7 is overclocked, but feel free to adjust clockspeeds on either system in the comparison.[/QUOTE]
I have an AMD Phenom II X6 1045T, perhaps I can be of assistance somehow? It's not exactly a "standard" Phenom II, in that this particular model is only sold in pre-built PCs. But I'd imagine it's fairly comparable?

[QUOTE=James Heinrich;252404]Not exactly the same, but gives you some idea: you can compare single-core performance of an [url=http://mersenne-aries.sili.net/throughput.php?scale=1.2795650924844&cpu1=AMD%20Phenom%28tm%29%20II%20X4%20940%20Processor|512|6144&mhz1=3000&cpu2=Intel%28R%29%20Core%28TM%29%20i7-2600K%20CPU%20%40%203.40GHz|256|8192&mhz2=4400]AMD Phenom X4-940 and an i7-2600K[/url] on my site. I don't have any X6 benchmarks, but I don't think they vary too far (comparing single cores) from the X4. Note the i7 is overclocked, but feel free to adjust clockspeeds on either system in the comparison.[/QUOTE]
Here's one (oops it's actually a 1090T OC'd to 3400 [17x200] instead of 3200[16x200]).

Found out a problem with my machine.

During 25.11 testing, the voltage drops about 0.10V or so (hard to see exact figure as it reboots shortly after that). And hence the PC blue screens after that.

Similarly with the other test I did. (4.5GHz 26.5.2). Only difference is when.

Enabling Vdroop to level2, kept the voltage within a tighter bounds (0.03V). Voltage now increases with load and increases slightly. Without Vdroop the CPU voltage was decreasing due to load. (gradually and during the load, take away load - voltage went up)

The PC survived @4.8GHz with Vdroop-2 for at least 3hrs or so before blue screen.

Dropping to 4.5GHz the machine appears to be more stable. Now it's lasted 12+hrs (torture test started 7:30am, it's now 8:10pm). No reported errors so far.

From reading around overclocking forums, 4.5GHz seems pretty common as a 24/7 overclock.

So I think it's fairly stable now. Anyone got any ideas how long I should leave the torture test go for before putting this machine to work?

-- Craig

From what I remember of the previous i7s, enabling that option isn't recommended. Yes it means you get a higher voltage under load, but when the load is suddenly removed, it can't react fast enough and you get a large momentary spike in voltage.

Possibly things have changed since the last generation, but it's certainly something I'd recommend checking up on.

Is raising the voltage permanently not an option?

[QUOTE=henryzz;252462]Is raising the voltage permanently not an option?[/QUOTE]

I guess I could raise it above some more points, and let it sag during operation.

-- Craig

[QUOTE=sdbardwick;252446]Here's one (oops it's actually a 1090T OC'd to 3400 [17x200] instead of 3200[16x200]).[/QUOTE]Thanks, benchmark added. Now you can see a direct comparison between a (single core of an) [url=http://mersenne-aries.sili.net/throughput.php?scale=1.2795650924844&cpu1=AMD%20Phenom%28tm%29%20II%20X6%201090T%20Processor|512|6144&mhz1=3500&cpu2=Intel%28R%29%20Core%28TM%29%20i7-2600K%20CPU%20%40%203.40GHz|256|8192&mhz2=3500]X6-1090T and i7-2600K[/url], at identical clockspeeds the AMD only does 70% of the FFT work of the Intel. Of course, the AMD does have more cores available. But the Intel can almost certainly run faster. But the AMD is cheaper. And so it goes :smile:

@KingKurly: your benchmark(s) would also be welcome, you could post here, or in the [url=http://www.mersenneforum.org/showthread.php?t=59]Perpetual Benchmark Thread[/url] or just [url=http://mersenne-aries.sili.net/throughput.php]email to me[/url].