I maintain some nasty oldish hardware:

VIA C7 CPU @ 1500MHz
VIA CN700/P4M800 Pro/P4M800 CE/VN800 Graphics [S3 UniChrome Pro] (rev 01)
VIA VT8233/A/8235/8237 AC97 Audio Controller (rev 60)
Ethernet controller: VIA Technologies, Inc. VT6102 [Rhine-II] (rev 78)
The P4M800 graphics chip was unusable in Saucy:


But it's fixed in Trusty which now shows it's using Gallium on llvmpipe:


The general performance is really good in both Ubuntu flashback/w metacity and Lubuntu but if I change the resolution from the default 1366x768 on my 18.5 LCD display to my desired 1280x720 I then just get a blank screen, and that persists on reboot

There is no xorg.conf and trying to reset X through the recovery mode doesn't work so I'm clueless where to start

I'm a total dummy when it comes to filing bugs against X also