Which of these CPUs is most productive?

[mdettweiler]

Originally Posted by lavalamp

If you want a GUI, you can set all the computers up using a monitor, keyboard and mouse, but then unplug them when you're done. This way the machines don't take up a huge amount of room, and you don't need to buy lots of monitors, keyboards and mice. All they should need is power and a network cable (I GREATLY prefer wired over wireless).

Then you can VNC into them from your main desktop PC. There are lots of VNC applications, many of them free and open source, they work on all kinds of different platforms so you can VNC into a Linux box from a Windows PC no problem.

VNC allows you to see what would be on their screen, if they had one attached (or even if they do have one attached but you're too lazy to go there ).

Yeah, this is kind of what my friend does. He has VNC set up on all the machines to access them while he's out of town (as he goes on frequent business trips). However, while in town, he generally uses the consoles--probably since they're faster and, after all, they're just downstairs. From what I understand, he thusfar has had plenty of room in his basement and hasn't had much need to conserve space, so having three or four old CRTs laying around hasn't been a problem.

Nonetheless, indeed, you can do a lot with VNC...I access his machines on a regular basis from halfway across the U.S. and while it's a little slow, it's not too bad. What we do is have one machine (the server box) which is exposed to the internet via SSH, and all VNC access is tunneled through SSH to the server. (I wrote up a script for my friend so that he can do this easily without having to type any of the tunneling commands.)

[henryzz]

Originally Posted by mdettweiler

8 GB should actually be plenty for most modern Linux distributions; even Windows 7 should be able to fit (I have a Windows 7 Enterprise trial version installed on a virtual machine and it only takes up ~5.5 GB).

That's small. Have updates etc been installed? My windows directory alone is 17 GB. Unless you are putting program files on another drive I wouldn't suggest getting even a 80GB drive for a well used pc. 80GB should do a cruncher 40GB would be pushing it for even a cruncher. I currently am using 72 GB out of 100 GB partition. I ran out of space on a 80 GB partition cleaned it up and expanded it recently. I have ubuntu on that disk as well.

[mdettweiler]

Originally Posted by henryzz

That's small. Have updates etc been installed? My windows directory alone is 17 GB. Unless you are putting program files on another drive I wouldn't suggest getting even a 80GB drive for a well used pc. 80GB should do a cruncher 40GB would be pushing it for even a cruncher. I currently am using 72 GB out of 100 GB partition. I ran out of space on a 80 GB partition cleaned it up and expanded it recently. I have ubuntu on that disk as well.

Hmm, I see. My virtual machine is pretty much brand-new (with some Windows updates installed I believe, but no additional programs). I didn't realize Windows updates made the Windows directory grow in size...I always assumed they just replaced whatever part they were fixing. (Though I suppose it makes sense that all their installers are being kept around somewhere, in case they need to be uninstalled.)

Agreed, though, that 8 GB would be very small for Windows 7. It probably could work in a pinch, but would run into problems quickly. 8 GB should, however, be plenty for Ubuntu or most other Linux distributions if you're not planning to install many programs (like on a crunching box).

[Christenson]

You want small? Try minix...but someone like me will need to get the USB drive boot part working...and do the Prime95 port....you can't buy a drive that won't swallow it..

[Rodrigo]

Originally Posted by mdettweiler

Note that even with a dedicated crunching box, you may want to have an actual disk (SSD or hard drive) to give added flexibility. For instance, a friend of mine on this forum has a "small" farm of 10 dedicated crunching machines, which I consulted on the setup of. Since he's not too particularly tech-savvy, we ended up forgoing the more exotic possibilities (netboot, USB, etc.) and built complete, but nonetheless Spartan computers. Each box has a CD drive, hard drive, and case, but we picked the cheapest ones availalble at the time. From there, we could have still made the boxes headless (no monitor/keyboard/mouse) but he wasn't comfortable with going all-command-line so we ended up installing Ubuntu Desktop. He has them all in his basement with three or four monitors shared between a few boxes each via KVM switches.

mdettweiler,

Consider my mind officially blown. It's amazing what one can do with computers after mixing inventiveness with knowledge.

Here I am thinking about putting together a home powerline network (a notion that already makes my friends' eyes glaze over) so that we can work out in the gym while watching a show that was recorded in the family room... and then I hear about the setup you created, which is more exotic by a degree of magnitude.

Fabulous!

Rodrigo

[Christenson]

I worked a bit on OFDM powerline chips some years back....now you can find them in Best buy, all packaged up and ready to go....I like the KVM solution, being really straightforward.

Mdettweiler...Can you consult on the best CPU (not quite headless; I'll browse and stuff on it) for between $500 and a Grand or so? I'm going to buy a pre-working system, newish, and put it to work on Prime95 and possibly NSF@home. I know that I can get a Core Quad for that price...wondering if Phenom II x6 is better...

[mdettweiler]

Originally Posted by Christenson

Mdettweiler...Can you consult on the best CPU (not quite headless; I'll browse and stuff on it) for between $500 and a Grand or so? I'm going to buy a pre-working system, newish, and put it to work on Prime95 and possibly NSF@home. I know that I can get a Core Quad for that price...wondering if Phenom II x6 is better...

Hmm...not much available in the $500-$1000 range* any more (since most CPUs have dropped in price to below that point) though if cost isn't a big limiting factor, the i7-970 and i7-980X would be the most powerful CPUs you can get right now. They've got 6 cores (with hyperthreading) and are faster per-core than the fastest AMD X6--though at a price ($899 and $999 respectively).

However, for only a small performance hit, you can get a top-of-the-line AMD X6 (the 1100T) for just $269. At that price, you can get two or maybe even three machines for the price of one Intel. That may or may not be an option in your case (if, say, you only have space for and/or can afford the power costs of one machine), but it's worth considering even if you're only getting one machine since it will save you a LOT of money.

Another possibility to consider is the new Intel Sandy Bridge CPUs, but note that they aren't available in 6-core models yet, and even at 25% faster per-core than a previous-generation i7 (that seems to be the amount of speedup people are getting on Prime95), you get 4*.25=1 additional core equivalent--which while close, is still not quite enough to top the total computational power of an AMD X6.

*Note: I'm assuming here that you mean for the CPU to cost between $500-$1000. Did you by chance mean you're looking to spend that much on the entire system (not just the CPU)? If so, then you'll definitely want to go with the X6--no contest since the only Intels that can compete in terms of total computational power are the i7 6-cores, which as mentioned above cost at least $900 in and of themselves.

[lavalamp]

Christenson, I'm not mdettweiler, but here are two systems, one Sandy Bridge Intel and one 6 core AMD, only the CPUs and motherboards differ and they both have the exact same price, $510.93 before tax and shipping.

I have included a hard drive, but not a DVD drive. You can install windows 7, and a lot of Linux distro's too I believe, from a USB pen drive. Or if you have a DVD drive to spare, you could temporarily hook it up to install the OS. Or just add a DVD drive to the parts list, but I was trying to keep the cost down while keeping the highest performing system.

Intel:
Intel Core i5-2400 Sandy Bridge 3.1GHz (3.4GHz Turbo Boost) 4 x 256KB L2 Cache 6MB L3 Cache LGA 1155 95W Quad-Core Desktop Processor BX80623I52400
$194.99

GIGABYTE GA-H67M-D2 LGA 1155 Intel H67 SATA 6Gb/s Micro ATX Intel Motherboard
$94.99


AMD:
AMD Phenom II X6 1090T Black Edition Thuban 3.2GHz 6 x 512KB L2 Cache 6MB L3 Cache Socket AM3 125W Six-Core Desktop Processor HDT90ZFBGRBOX
$229.99

ASRock 880GM-LE AM3 AMD 880G Micro ATX AMD Motherboard
$59.99


Rest of system:
GeIL Value PLUS 8GB (2 x 4GB) 240-Pin DDR3 SDRAM DDR3 1600 (PC3 12800) Desktop Memory Model GVP38GB1600C9DC
$98.99

COOLER MASTER Hyper 212 Plus RR-B10-212P-G1 "Heatpipe Direct Contact" Long Life Sleeve 120mm CPU Cooler Compatible Intel Core i5 & Intel Core i7
$29.99

SeaSonic SS-350ET Bronze 350W ATX12V V2.31 80 PLUS BRONZE Certified Active PFC Power Supply - OEM
$42.99

Rosewill R102-P-BK 120mm Fan MicroATX Mid Tower Computer Case
$29.99

Western Digital AV RFHWD1600AVBS 160GB 7200 RPM 2MB Cache SATA 3.0Gb/s 3.5" Internal AV Hard Drive -Bare Drive
$18.99

Key points:

• Brand new quad core from Intel (without hyperthreading) vs. high end hex core from AMD. Personally I don't think there's much in it, so I'd probably go with the Intel. Note that the AMD has an unlocked multiplier, so it has more freedom to overclock.
• PS/2 keyboard AND mouse inputs, as well as VGA output. Deliberately picked motherboards with these antiquated ports on since most KVM switches still use PS/2 and VGA, the USB + DVI KVM switches seem to cost a lot more.
• 8 GB of RAM in case you want to do RAM heavy stuff, can drop this to 4 GB, 2 GB or even 1 GB to save some more money if it's not needed.
• Beefy aftermarket CPU cooler to cool whichever system is under it, supports sockets AM3 and LGA 1155.
• 350 W Seasonic 80 Plus PSU, good brand but a little weak if you want to be adding a graphics card for crunching too. Think about moving to 500 W if you will be.
• Dirt cheap POS case, not exactly robust, but great for a compute box that is basically left alone all the time.
• Cheapest SATA HDD on Newegg, MUCH larger capacity than needed, but who cares?

Finally, since you seem to have a grand to blow, why not get them both and you can give us a full comparison?

[lavalamp]

Note, overclocking Sandy Bridge CPUs with the base clock is not possible. Instead you must use the CPU multiplier, which means you need a chip that isn't locked. These are denoted by the letter K, and the cheapest is the i5-2500K for $30 more than the i5-2400 in the parts list above.

Unfortunately there are some knock on effects then. It's not all bad news, I actually found some cheaper parts, but I'll spare you the details, here is an updated parts list:

Intel:
Intel Core i5-2400 Sandy Bridge 3.1GHz (3.4GHz Turbo Boost) 4 x 256KB L2 Cache 6MB L3 Cache LGA 1155 95W Quad-Core Desktop Processor BX80623I52400
$194.99

GIGABYTE GA-H67M-D2 LGA 1155 Intel H67 SATA 6Gb/s Micro ATX Intel Motherboard
$94.99


Overclockable Intel:
Intel Core i5-2500K Sandy Bridge 3.3GHz (3.7GHz Turbo Boost) 4 x 256KB L2 Cache 6MB L3 Cache LGA 1155 95W Quad-Core Desktop Processor BX80623I52500K
$224.99

ASRock P67 PRO3 LGA 1155 Intel P67 SATA 6Gb/s USB 3.0 ATX Intel Motherboard
$123.99

COOLER MASTER Hyper 212 Plus RR-B10-212P-G1 "Heatpipe Direct Contact" Long Life Sleeve 120mm CPU Cooler Compatible Intel Core i5 & Intel Core i7
$29.99

XFX PVT86SWHLG GeForce 8400 GS 256MB 64-bit DDR2 PCI Express 2.0 x16 Video Card
$24.99


AMD:
AMD Phenom II X6 1090T Black Edition Thuban 3.2GHz 6 x 512KB L2 Cache 6MB L3 Cache Socket AM3 125W Six-Core Desktop Processor HDT90ZFBGRBOX
$229.99

ASRock 880GM-LE AM3 AMD 880G Micro ATX AMD Motherboard
$59.99

COOLER MASTER Hyper 212 Plus RR-B10-212P-G1 "Heatpipe Direct Contact" Long Life Sleeve 120mm CPU Cooler Compatible Intel Core i5 & Intel Core i7
$29.99


Rest of system:
GeIL Value PLUS 8GB (2 x 4GB) 240-Pin DDR3 SDRAM DDR3 1600 (PC3 12800) Desktop Memory Model GVP38GB1600C9DC
$98.99

Antec EarthWatts Green EA-380D Green 380W Continuous power ATX12V v2.3 / EPS12V 80 PLUS BRONZE Certified Active PFC Power Supply
$39.99

GIGABYTE GZ-KF03B Black SGCC ATX Mid Tower Computer Case
$19.99

Western Digital AV RFHWD1600AVBS 160GB 7200 RPM 2MB Cache SATA 3.0Gb/s 3.5" Internal AV Hard Drive -Bare Drive
$18.99

Prices:
Intel system $467.94
Overclockable Intel system $581.92
AMD system $497.93

Changelog:

• Basic Intel system relies on stock cooler, since it can't be overclocked, may as well save money and stick with it.
• Overclockable Intel system requires a discrete graphics card since it does not have onboard graphics.
• Cheaper, but still good brand and 80 Plus, PSU on the list.
• Cheaper case, and it supports full ATX motherboards too.

It's a shame that Intel now want to force you to pay more for overclocking, especially when overclocking is supposed to bring extra performance for free. However, overclocking itself should be easier, since everything has it's own separate multiplier and the motherboard has little, if any, effect.

The CPU on the parts list for the AMD system is also an unlocked chip, however there are two other 6 core chips that are $30 and $50 cheaper that are locked. If you want to save money by switching to those, you will still be able to overclock them by adjusting the FSB, it'll just be harder.

[Rodrigo]

lavalamp,

Great rundown. Thanks for gathering up the parts info.

I looked up the AMD six-cores. I didn't know about the overclocking capability (or lack of it), but FWIW besides the price they also seem to have different clock speeds (3.2/3.0/2.8 GHz). I'm not sure how much of a difference that would make for the purposes of GIMPS.

One question: When setting out to build one's own computer, is there a trick to matching up the motherboard with the case, or is it a case (sorry) of any mobo working with any case, so long as you have the right sizes (ATX, micro ATX, and so on)?

Rodrigo

[Mini-Geek]

Originally Posted by Rodrigo

One question: When setting out to build one's own computer, is there a trick to matching up the motherboard with the case, or is it a case (sorry) of any mobo working with any case, so long as you have the right sizes (ATX, micro ATX, and so on)?

The mobo and other components fitting is the main requirement for choosing a case. Secondary requirements are what USB/audio ports it may have on the front, how it looks, etc., nothing else too closely related to the mobo (unless you consider case as case+power supply, a common bundle; in that case, you're really asking about the power supply).