Intel Core i7 3820 review & benched; The cheap x79 processor vs 8150/3960X/etc....
I recently needed to replace an aging Phenom II x4 machine. My eventual goal was a machine supporting 4x Nvidia cards for CUDA processing. Since the Gigabyte motherboard supports 4-way SLI, I felt assured I could support this need. (Yes, I know CUDA ignores SLI). I would have rather used an AMD 8150 to save money, but the cheaper motherboards translated to horrid 4x graphics card support and questionable quality. Needless to say I jumped on the x79 platform when Intel released a reasonably priced CPU for socket 2011.
- Core i7 3820 @ 3.6GHz (stock)/4.5GHz (43x 104 BCLK & 1.28v), $320
- Gigabyte x79 UD3, 4-DIM, 4-way SLI, average overclockability, $265
- Corsair H100 CPU cooler. This model usually has a noisy pump which is caused by more than 12v on the line. Resistor or fan controller fixes issues. Temps at max are 50C. $100
- Corsair 4x4GB DDR3 RAM, 1600MHz, 9-9-9-24, $100
- G2 Microcenter SSD, SATA2, $100
- Nvidia GTX 460 1gig RAM, $150
- Ubuntu 12.04 doesn't report the correct CPU MHZ. I GUARANTEE my 3820 was NOT running at 6GHz ;) !!!!
- Socket 2011/X79 platforms are great work station platforms. 40 lanes PCIE means far more graphics cards & SATA connections. This is much more than socket 1155/Z68/P67 platforms can provide.
- Intel i7 3820 is not based off the same die as 3930k/3960k. Its more Sandybridge like with 2megs extra cache and lots of supporting silicon for the PCIE support.
- Intel i7 3820 performs much like a 2700K and might not over clock as high because of all the extra silicon. TBD. Some have said 5GHz is easy for the 3820, I don't want the heat issues.
- Intel i7 3820 has a max overclock multiplier of 43. It will do 4.3GHz easily on the stock voltage. Other tricks using BLCK are needed to go further.
- Gigabyte x79 UD3 has a couple weak points. Only 4 DIM slots and possibly poorer over clocking based on the number of mosfets on board.
Here are the results. I benchmarked at both stock and at 4.5GHz to compare against Michael's 3960X:
- NAS results should have matched the 2500K. Perhaps the Hyperthreading was causing issues for the 3820? Regressions?
- The 3820 trounced all chips in FFMPEG except for the 8150 (very close). At 4.5GHz, the 3820 kills all! ;) Perhaps there is a regression for the 3960k here.
Overall I'm very pleased. The Core i7 Extreme 3960X comes in at $1000 USD, whereas the Core i7 3820 can be found for $320 USD. The 3960X is not 3x the processor, in fact the 3820 meets and exceeds the 3960X in many tests! I am not delusional though. I certainly would rather have the extra 2 cores and easier over clocking of the 3960X. Perhaps one day when I'm rich off of a website!
(Michael, since the 8150 and the 3820 chips are similarly priced, I'd like to compare them. Particularly I'd like to compare against these tests [ http://www.phoronix.com/scan.php?pag...clocking&num=1 ]. I for the life of me can't find the benchmark URL/Code to use to launch these tests. Do you have it?)