High latency spikes on Gigabit crossover

[Z3R0]

I've managed to get this working fairly well, except for some stuttering and network latency spikes >100ms. This is really weird because the Gigabit "network" I have set up is a crossover cable between the host and the client. There should be no latency spikes at all on such a connection. I have a really old iMac that has a nice screen (24", 1920x1200) that I wanted to use for playing games. Its old Core 2 Duo and ATI Radeon HD 2600 are too weak to play most modern games, and is limited by the weak selection of Mac games. So now I can run Fallout 4 on my 9 year old iMac. Nifty. However the network lag is occasionally causing some pretty serious stuttering. How should I begin troubleshooting this? FPS are usually pretty good, usually about 45 fps, with dips to 30 fps and surges to 55 fps.

[Trogdor0]

I don't know about your problem specifically, but I can say that you probably don't need to have a special crossover cable. A regular network cable will do. Automatic MDI/MDI-X is part of the gigabit networking spec. And even though it is optional, 99% of the gigabit NICs out there do implement it.

[Z3R0]

Thanks for the thought, but I suspected that the Mac didn't require a crossover cable anyway. After some experimentation, I found a less than satisfying workaround. If I drop the resolution to 1440x900 almost all the spikes and stuttering go away. While it makes the game more playable, I'd much rather be able to operate at 1920x1200. I tried streaming to a laptop with a much more powerful CPU and GPU with the same resolution (1920x1200), and had the same issue, so I don't think that the Mac's specs are the issue. Maybe Steam streaming doesn't like resolutions over 1080p??