Thanks for writing to us.
This is what we supported =
Four slots Black 3, White 1, Black 4, White 2
DDR3L, unbuffered, Non-ECC, quad-channel, 1.5v
66GKY 8GB, 1600MHz, 512X64, 8, 240, 2RX8, PC3-12800U (Nanya NT8GC64B8HB0NF-DI or Kingston K66GKY-HYA)
VT8FP 4GB, 1600MHz, 256X64, 8, 240, 2RX8, PC3-12800U (Nanya NT4GC64B8HG0NF-DI or Samsung M378B5273DH0-CK0)
531R8 4GB, 1600MHz, 256X64, 8, 240, 1RX8, PC3-12800U (Micron MT8JTF51264AZ-1G6E1 or Hynix HMT451U6AFR8C-PB)
GDN7X 2GB, 1600MHz, 256X64, 8, 240, 1RX8, PC3-12800U (Nanya NT2GC64B88G0NF-DI or Samsung M378B5773CH0-CK0 or Hynix HMT325U6CFR8C-PB)
Should you have any questions do give us a shout.
Do provide us your system tag#, email address and name via private message,by clicking on my name in blue and then select send a private message
DDR3 1600 is all that works out of the box.
The BIOS has no screens to change memory timings or multipliers, and the BIOS does not allow overvolting the memory which is needed for XMP settings.
You can use Intel XTU to increase the multiplier, and I was able to get the OEM memory to run at 1866Mhz.
I'll see if I can dig up screen shots of the timings.
I can't find the screenshots. I gave this system to a family member and I don't think I kept all the screen shots, but here is post I made on another forum along with some test results and my final timings.
I think the dell forum will block the link, so replace the word DOT with a period and paste this into your browser.
forums DOT hardware-revolution DOT com/showthread.php?tid=5321
I ended up staying at 1600 Mhz but tightening up the latency to 7-9-8-18.
Dell factory timings are DDR3-1600 11-11-11-28
keep in mind, not all RAM is created equal so you may do better or worse depending on your memory.
One more thing. I didn't put in the notes but I was eventually successful getting 1866 Mhz, but the latency was really sloppy and the performance was not better. Everything I've read indicates faster memory frequency ( speed )needs a little more voltage, and that isn't an option on the 8700 Mobo.
And to compare some results on my non-dell system I'm able to take DDR3-1600 Mhz memory to 2400 Mhz andthe memory voltage needs to be increased from 1.5V to 1.63 volts. The latency goes up too and overall the system performance is slightly better according to benchmarks. However, in actual use the performance difference is barely noticeable. This is an i7 4790K running at 4.7Ghz with a Z97 chipset.
So my point is, you might be able to boost the memory speed a little, but in the end I think you'll find the net result is minimal.
But, give it a try you might find it works better for your needs.