How much will DDR3-1600 RAM bottleneck a 4790k?

[Merad]

I'm looking at a high end system build in the next 2 months and at the moment am considering basing the system around either a 5820k or a 4790k. If I can recycle my current RAM then the 4790k system is the clear winner at about $400 cheaper. But if I really need to do a RAM upgrade along with the 4790k, it's worth thinking about some more since the 5820k won't be that much more expensive...

 

[Cerb]

The i7-4790K can take 2 more sticks, for 32GB, if you need it.

Whether it may present a bottleneck depends on what you have, what you do with it, and how much performance in a few niche cases it would take to spend more.

 

[escrow4]

DDR4 latencies are atrocious, unless you love CAS 15. There will be no bottleneck outside of benchmarks and the odd application where you won't be able to tell anyway. And X99 boards are half broken now anyway, the firmware is even worse than the RAM.

 

[Lepton87]

What do you mean half broken? DDR3 1600 will not bottleneck an 4790K except for a few benchmarks, just like escrow said. I would be more concerned with the amount of RAM you have not the speed, if you have at least 8GB you should be fine, 4GB is IMHO a bit too little nowadays.

 

[escrow4]

What do you mean half broken? DDR3 1600 will not bottleneck an 4790K except for a few benchmarks, just like escrow said. I would be more concerned with the amount of RAM you have not the speed, if you have at least 8GB you should be fine, 4GB is IMHO a bit too little nowadays.

X99 BIOS firmware is all over the place. On topic, I agree, 8GB is the new minimum and 16GB is the sweetspot for DDR3.

 

[Lepton87]

I wouldn't say 8GB is the minimum if I had 6GB I wouldn't worry too much about it. 4GB is workable but a bit too little for comfort.

 

[BonzaiDuck]

X99 BIOS firmware is all over the place. On topic, I agree, 8GB is the new minimum and 16GB is the sweetspot for DDR3.

That's always been the case -- or mostly -- for a new chipset and processor line. In fact, for the X99, all three parts are "firsts" including the DDR4. At least the E processors are the result of two waves of Haswell chips.

I usually wait for BIOS revisions to mature. If the bugs are entirely in the firmware, it can all shake out pretty well. If I had more tolerance for headaches and puzzlements, I wouldn't wait so much. But no shame in my other constraints: I have to pay for $2,000 in dental repair this month. Even more reason for me to "stick to my plan."