Broadwell I5-5675C/i7-5775C & Oculus Rft DK2 & ED - any experience already?

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Hello,

I am currently considering upgrading my G3258 to a I5-5675C and am curious if any one else is already using a Broadwell CPU here.
The low TDP and gaming results look very promising for my small form factor ED box although it is really hard to find some decent reviews I have to admit digging into it for about 3 weeks now.
This CPU would really need more attention (or availability outside europe, haha)

The more interesting reviews I found were made in poland and sweden in local language but I think the CPU would fit for my purpose / box.
Currently I have a R9 290 and the G3258 (OC to 4.4, sadly a bad overclocker sample that I have) in a MicroATX Case (Corsair 240) with a Noctua NH-U9S CPU Cooler and some Alpenföhn Wingoost 2 Fans for cooling the R290 while keeping noise in control.

Also I speculate a bit that the iGPU on the broadwell will be useable somewhere on CV1 release to be used for rift postprocessing/distortion be it in DX12 (maybe not ED then but who knows) or otherwise. Thats really a farfetched assumption though and I know it ;)

So anyone did take the adventure to use Broadwell here yet and can share experience.
Of course I would like to directly try the 4690K against myself if I had the money lying around..
The I7-5775/4790K comparison I would consider not to be an option as for TDP on overclock and price which seems to be too high for the performance I expect for gaming/ED only.

The more interesting sources with OC benchmarks:
http://www.sweclockers.com/test/20908-intel-core-i7-5775c-och-i5-5675c-broadwell
http://pclab.pl/art64700.html
https://techreport.com/review/28751/...sor-reviewed/6
https://translate.google.de/transla...e/2015-10/intel-core-i5-6500-5675c-4690-test/
 
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Deleted member 110140

D
I have I7-5775c with GTX 980 and DK2. It runs ultra settings, no SS, full HMD Quality more or less at constant 75hz. I haven't tried Horizons beta though, so I can't comment on that. According to

https://techreport.com/review/28751/intel-core-i7-6700k-skylake-processor-reviewed/6

the Broadwells (i7-5*75c) may currently be the best CPUs for VR gaming money can buy, due to their large L4 cache. Running the smoothest framerates with least framedrops.

Don't know for i7-5675c, but i7-5775c's turbo freq can be raised to 4.0Ghz by simply increasing the multiplier in BIOS, no voltage changes required. Also running at really low TDP. Highly recommended.
 

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Thanks bazel, added link(s)

In the meantime I bought an I5-5675C and wanted to write up something about it but didn't have the time yet.

Well, I really like it and at times you could get th I5-5675C for under 200€ in Germany in the last weeks.
Also some more review surfaced but still the CPU seems to be neglected by most of the newer tests.
IMHO a real shame - it's a very good choice for a Z97 chipset upgrade but still you need to be careful:

The overclocking is not easy - it behaves more like a woman!
You need to treat it carefully and have endurance and love to care for it.

Especially you should check first before installing/considering if your latest BIOS update supports Broadwell CPUs at all.
The Bios should be released after August to enhance your experience as there are some bugs in the speedstep functionality which only are fixed in Intels latest microcode updates that need to be included in your BIOS for windows as you cannot load it yourself.
So theres some luck you need - for my MB (Asrock Z97M Killer Fatal1ty) I was lucky and the official 1.90 has a more recent microcode update built in.
Otherwise you need to lock it to your max multiplier or you might get BSOD when its clocking low. (workaround 1)
Next you need to have support for setting the TDP value to something above 65W (5675c) if you intend to overclock - you could archive this though Intel XTU utility when you MB does not support (was available but didn't work on my MB previous BIOS version) (workaround 2).
To be able to overclock the L4 EDRAM cache you will need to check again if that is possible - I got a beta BIOS from ASrock support where they enabled it but still any change to the EDRAM multiplier does not work and I have received no further answers after multiple feedback.
If it would not be working with my current BIOS I would not recommend Asrock for the MB as support seems limited and slow.

For overclocking the voltage wall for me is at 4.1GHz 4.1 is stable with 1,235v but going higher(like 4.2) needs much more (1.3+) to be able to keep on prime95 which is not feasible for me on air cooling due to fan speeds etc.

Aside from that - when its running its a really cool CPU - temps are low - TDP used is low. Great for my small form factor build (Corsair 240 case).

I still have hopes for elite and VR that someday I can use the iGPU in addition to offload some tasks by DX12 maybe. Pure speculation though as it would involve Frontier dev and VR would need attention on some other topics more urgently for them.
 

Deleted member 110140

D
Great to hear about your experience. It seems from the specs, that i5-5675c is pretty much the same as i7-5775c, just without Hyper Threading, which probably does more bad than good for a gaming setup. Seems to overclock just about the same, I've read you need to bump voltage for 4.1Ghz OC for i7-5575c too. You might want to try a lower OC at 4.0 or 3.9, maybe you can have it stable without raising the voltage. It should be more than enough for ED.

I didn't raise voltage or TDP for a 4.0Ghz overclock. CPU will throttle down in an 8-threaded torture test with mprime, however a single-threaded workload keeps it at 4.00Ghz. My guess is there is simply no way it would throttle during a gaming session, I expect bottlenecks in a game pipeline to be single-threaded and temporary. Still, it would be good to have a benchmark in ED to quantify these things.

I'd say, you don't want to use iGPU at all. Not using it, makes all the L4 cache available to CPU, which is what makes these Broadwells perform so well.
 

Deleted member 110140

D
Thanks, that's very useful. It doesn't throttle with ED, neither with XTU's builtin stress test. Only with mprime.
 
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