Time for new hardware re:random crashes

imac early 2008 osx 10.11.6

I am experiencing random crashes sometimes to white screen, sometimes to black. So far simple toggling off/on and everything comes back/boots normally. There seems to be no consistent reason ie; any particular application or website, it is completely random. Ran an etrecheck with no standout problems, the only questionable dialogue was an ominous "this hardware is obsolete".

Am I asking too much of an 11 year old Mac (how much is that in computer years).