[QUOTE=Mini-Geek;372657]I got everything running over the weekend, and it's looking very good so far! The CPU is running at 4GHz (at 4.2GHz I got a BSOD after a few minutes of Prime95's stress test), using the motherboard's built-in OC settings, and the RAM is at 2400Mhz with the default XMP profile.

At 4GHz, the cooler keeps the CPU at about 80C (ambient is 25C) on 84K FFTs or about 70C on DC-sized (2M) FFTs.[/QUOTE]

If you find the time, it might be of interest to you to play with the voltage a bit longer. My board has an overclock feature but it was way to aggressive with the voltage. If memory serves, it put me at 1.38 V and 4.6 GHz. Manually I was able to achieve 4.6 GHz at 1.28 V and 4.5 GHz at 1.20 V.

Take it down a few notches at a time and see where it stops being stable, and go a few notches back up from there.

Alternatively, leave everything where it is and enjoy your new rig!

[QUOTE=TheMawn;372666]If you find the time, it might be of interest to you to play with the voltage a bit longer. My board has an overclock feature but it was way to aggressive with the voltage. If memory serves, it put me at 1.38 V and 4.6 GHz. Manually I was able to achieve 4.6 GHz at 1.28 V and 4.5 GHz at 1.20 V.

Take it down a few notches at a time and see where it stops being stable, and go a few notches back up from there.

Alternatively, leave everything where it is and enjoy your new rig![/QUOTE]

Haswell has a thing called adaptive voltage, is a damn pain to have if you use FMA3... It just really takes a lot longer and a bit of creative thinking if you want it on.

Well, my Ivy Bridge has this offset voltage thing that I've gotten back into. It takes a base voltage and applies a +/- value to it under load. I believe it's a function of the multiplier in some regard.

I'll look up this adaptive voltage some other day, to see if it's the same. The offset voltage was enough of a curve to learn. Hopefully this one isn't worse.

What I'm reading here is encouraging and I'm due to upgrade (last time was 2006).

This is interesting: i7-4770K, 16 GB DDR3 - 2400, boart to be determined but will be a server type. Last boart was Asus P5MT, not much in bios settings but did last running prime 24/7 for nearly 8 years

Can I get away with stock cooling? I may have to buy the parts overseas and DHL them here. A heavy copper block cooler would add to the shipping (140 $ / kg). It is not hot here in Rwanda, daytime 25 / 27 degrees and 16 / 18 at night, uniform all year round. I may overclock modestly but no pushing things as seems to be done around here.

What I like to do is P-1 and ECM. Perhaps 16 GB ram is not enough - 32 sounds better. Any feedback on this particular is appreciated.

[QUOTE=PageFault;373687]What I'm reading here is encouraging and I'm due to upgrade (last time was 2006).

This is interesting: i7-4770K, 16 GB DDR3 - 2400, boart to be determined but will be a server type. Last boart was Asus P5MT, not much in bios settings but did last running prime 24/7 for nearly 8 years

Can I get away with stock cooling? I may have to buy the parts overseas and DHL them here. A heavy copper block cooler would add to the shipping (140 $ / kg). It is not hot here in Rwanda, daytime 25 / 27 degrees and 16 / 18 at night, uniform all year round. I may overclock modestly but no pushing things as seems to be done around here.

What I like to do is P-1 and ECM. Perhaps 16 GB ram is not enough - 32 sounds better. Any feedback on this particular is appreciated.[/QUOTE]

In my experience with a 4670K, stock clocks are at borderline throttle with the stock cooler. A Hyper 212 EVO is not bad, not sure on how heavy though. Get a 4670K, not the 4770K, performance is almost same.

[QUOTE=PageFault;373687]
This is interesting: i7-4770K, 16 GB DDR3

What I like to do is P-1 and ECM. Perhaps 16 GB ram is not enough - 32 sounds better. Any feedback on this particular is appreciated.[/QUOTE]

In my experience, ECM responds very well to hyperthreading, so ideally you'd like enough memory to run 8 ECM processes. I would start with 16GB, and buy another 16 in a year or two as B2 and ECM memory requirements rise (are you testing Mersenne numbers, or for other projects?). Testing enormous B2 bounds is fun, and does present the chance to find a near-record factor- but whether that option is worth another $200 on a machine is personal.

If you have 4GB now, you could run a single process with your desired ECM parameters, measure memory use, and see how many you could run in 16GB. Perhaps you'd run 4 large processes and 4 smaller ones (say, 4 P-1 tests and 4 ECM) once you have 16GB.

[QUOTE=PageFault;373687]What I like to do is P-1 and ECM. Perhaps 16 GB ram is not enough - 32 sounds better. Any feedback on this particular is appreciated.[/QUOTE]
An ECM with the following bounds:

ECM2=1,2,9195881,-1,50000,5000000,150

Takes up to 10177 MB of memory in stage 2 (I allowed 12000 MB, that's all it took). Stage 1 took about 50 minutes of CPU time, and stage 2 took around 25-30 minutes. If you have 8 ECM processes running, you'll have approximately 3 in stage 2 at once (at this speed), using up to ~30GB. So having 32 GB of RAM for ECM/P-1 doesn't sound completely wasteful.

However, I'm pretty sure we're well into diminishing returns, and the extra 16 GB would be a small benefit, not a large one. I'm having trouble finding it, but someone looked at the % chance to find a P-1 factor when assigning different amounts of memory. For ordinary P-1s (around the first-time wave), having over 1GB (or 500MB? something relatively small like that) is practically irrelevant. This isn't a perfect analog, but it does show that extra memory doesn't speed things up dramatically. So I really wouldn't worry about 16 vs 32GB.

Note that I did this test with just one core doing ECM, so it's probably not taxing memory bandwidth, another big factor. For ECM/P-1, I think I'd rather have 8GB of DDR3 2400 memory than 32GB of DDR3 1600 memory. (I could be wrong about that, but that's my guess)

Thanks for the feedback guys - I really appreciate it.

A bit more money on ram is nothing - I can do it, if justified. And this seems to be the consensus - 32 GB minimum. I hear about cooling, in this case I want the best - cost inconsequential (it must last another 8 years). Big copper block recommendations please ...

I'll post back about the boart. I looked at three, one supermicro, two asus, at the same price point.

I will always use the official client - please educamate me on ECM and extreme settings - these interest me, I'm after the bizarre factor possibilities.

If you upgrade that infrequently I might suggest waiting for a DDR4 system. Haswell-E should be available this year probably Q3. Should you require to upgrade your memory at a later point it will then be possible cheaply. I am stuck with a DDR2 system currently(with a Q6600). Originally had 2GB of memory and later upgraded to 4GB. When I first bought the pc DDR3 was out and I should have got a motherboard that supported it in hindsight. I could do with more but by the time I needed it DDR2 was rare and extremely expensive compared with DDR3. You look like you could end up in the same situation. You could also end up with 6-8 cores as part of this if you go for Haswell-E although the initial outlay will be more.

What is your current system?

Not sure exactly on what you mean by "big copper block", custom water cooling?
If you want max life out of your investment, I wouldn't recommend overclocking too much, thus you may not need any exotic cooling.

[QUOTE]I'm having trouble finding it, but someone looked at the % chance to find a P-1 factor when assigning different amounts of memory. For ordinary P-1s (around the first-time wave), having over 1GB (or 500MB? something relatively small like that) is practically irrelevant.[/QUOTE][url]http://www.mersenneforum.org/showpost.php?p=282335&postcount=10[/url]