i7 5820K vs. i7 4790K

I built my system earlier this summer with an i7 4790K, 16GB DDR3 @ 2400, SSD for boot, SLI 780's, and an ASUS Maximus Hero VII, and I must say I am still impressed by the boot speeds and general responsiveness of the system.

Now my friend wanted to build a system but didn't know how to put it all together. Against my recommendation, he went with an i7 5820K, 16GB DDR4 @ 2400, same SSD for boot, GTX 970, and an ASUS Rampage V Extreme.

Considering that he had no idea how to put the thing together I figure this system is pretty far over his head, but that's besides the point; I noticed that his boot times are MUCH slower than mine and the general responsiveness of the system is far worse(speed of opening programs, closing programs etc.).

Could this be due to the massive 1.1Ghz difference in clock speeds? He doesn't know how to overclock it, and I haven't had time to do it for him. Should this be expected of a CPU like this running at 3.3Ghz?

No it has to with the SSD's

if that's the case you are seeing, that your SSD is faster than his, that tells me three things.

A. The SSD's you two own are different

B. if you two own the Same Branded SSD's. The Controllers in the SSD's are different.

C. If you two own the EXACT same SSD. Your friend probably doesn't have "Fast Boot" Enabled in the BIOS.

Doubtful it's his CPU.  It's plenty fast enough.  Maybe he didn't set his bios to AHCI prior to the install?  That can cause poor ssd performance.

Damn, he should have stuck with the 4790k! What a waste!

Not Necessarily, Programs and games are starting to leverage more cores, and the platform he is on won't die for another 5 years. He's basically good for a LONG while. it really makes no-sense to jump from Haswell-E to Broadwell-E. also it's 80 bucks more than the 4790K. 80 bucks for an extra 2 Cores why not.

Plus you get more PCIE lanes, quad channel memory and the Haswell-E parts OC very well.

It has to do with the SSD most likely. I'm guessing something to do with the, more than likely, Sandforce controller.


Maybe he didn't set his bios to AHCI prior to the install?  That can cause poor ssd performance.

This is really important and can make a massive difference to SSD performance. It can be rectified without re-installing windows:


5820k has indeed slower boot times then a 4670k.

Did you check his system is running in high performance after booting and all the stuff because sometimes balance mode caps the CPU CLOCK to consume less power so that might be the case 

The 5820k doens't OC well , hard getting it past 4.3 ghz , compared to i5's and i7's that get to 4.7-4.8 easy .

Also , much higher RAM cost ( double the price for 16gb ) and higher mobo cost ( minimum 230€ , compared to Z97 where you can get a good board for ~120€ )


But yes , you do get extra cores 

+1 clock speeds affect boot a lot , but I do think it has to do with the SSD

We both have Corsair LX series SSD's, though mine is a 512GB and his is a 256GB. I also have an LX series 256GB in a laptop with a similar, if not exactly the same, boot speed as my desktop.

Given that we're both running ASUS 'enthusiast' mobo's, and that I didn't have to set anything in my BIOS for the performance I'm getting in both my laptop and desktop, I am mildly doubtful of this being the cause. I will certainly look into the BIOS settings next time I am around his PC however, as perhaps X99 is a little screwy. Thanks!

If the user was a high productivity based person then I would agree that 'why not' could make sense, but this is a user who didn't know how to build the PC in the first place, likely won't do much more than gaming, and likely will never overclock unless I do it for him.

For gaming I would typically think fewer cores with higher clocks speeds would be best, especially given that most games hardly even use 3 cores currently. Of course this will change, but is there really any game a 4-core with hyper threading couldn't handle?

More PCI lanes are definitely nice, but this user will likely never take advantage of them, nor will he ever overclock or make use of the additional RAM capability.

I suppose it's a little more future proof, but the way I'm seeing it seems as if a person bought a performance package Corvette and never intends to drive it over the speed limit or take it to the track.

I probably should have checked that, but I had finished building the system/teaching him about building after a long day of driving, engineering finals, and work, so I wasn't exactly jumping at the idea of troubleshooting more after finally getting to the desktop. It's miles faster than his old and dying laptop so he's happy.

All of this was done for free of course, 'cause I'm just such a nice guy :P

For a first time builder, i agree your buddy shouldn't have gone with X99, but for someone who has built a PC built before and knows the in and outs of their componentry, i probably would of gone with a 5820k myself if i had the money just so i could stay on a platform that will last, unlike the mainstream platform that get's renewed every year and a half.