The memory controller is integrated into the CPU, so the motherboard chipset is irrelevant. There are some OEM-only v3/v4 parts with dual memory controllers, but the E5-2620 v4 is not one of them.
There are some OEM-only v3/v4 parts with dual memory controllers (because of a RAM supply crunch at the time, funnily enough), but the E5-2620 v4 is not one of them. The classic example is the very popular 12-core E5-2678 v3.
> Nowadays I'm not actually sure if DACs are cheaper than fibre now
Yep still are, although fiber transceivers are surprisingly affordable, and of course you can usually re-use jumpers when you upgrade transceivers so TCO over a couple generations might be comparable.
> I'm getting a really bad taste in my mouth for 10GBASE-T RJ45 SFP+ modules mostly due to the god awful heat they pump out
It's truly bananas especially in a homelab environment. Nearly every time I've thought to myself "oh I can just do a copper gbic for this" it's been the wrong thing to do.
If you start doing bonded links with DACs or if you have a bunch of servers, the cable management situation gets ugly in a hurry, and the usual solutions like patch panels and keystones aren't applicable. Source: my basement
I've started buying E810s even for 10G links. PCIe Gen4, lower power draw, RDMA support, generally backward-compatible with SFP+ DACs and transceivers, and relatively inexpensive. Not nearly as dirt-cheap as the X520s but not crazy expensive (last I looked, at least). As I gradually replace switches over the next few years I can start taking advantage of 25G.
They've been stable for me but I'd be lying if I said I'd only heard good things.
Looks like prices on the E810-XXVDA2 have come up since the last time I looked while prices on the ConnectX-6 Lx have come down, so that'd be a good option!
I use UniFi for most of my home network so It Just Works™, but I've thought about mixing in Mikrotik for e.g. the compute rack so I can play around with 100G+ links and more esoteric stuff like VXLAN.
I've started buying Intel E810s for most purposes, even for 10G links. (SFP28 ports are generally backward-compatible with SFP+ DACs and transceivers.) The ones you can get on eBay for cheap typically run Dell firmware but it's serviceable. An E810-XXVDA2 is Gen4 x8; as long as the host slot can physically accept the card connector you only need Gen4 x1 electrical for a single 10G link or Gen4 x2 for dual 10G or single 25G.
My homelab has a 10G fabric (switched) for NFS, iSCSI, NVMe-OF, etc. and a 25G fabric (a mix of back-to-back and switched) for clustering (Ceph, DRDB, ZFS replication, migrating VMs).
I spun up some iSCSI-backed SQL Server a few months ago and 10G couldn't keep up with the workload, so I dropped in a pair of 100G ConnectX-4 cards with iSER (iSCSI Extensions for RDMA) support for that particular use-case.
Just because your uplink is less than 10G doesn't mean the rest of your network can't be a bit more capable. :)
reply