Downloaded v5.1.0 but when I booted-up on the disc, it said v4.3.7. The MemTest website says older versions are automatically booted on systems that do not support UEFI (whatever that is, lol). Is that what happened to me?

Also, after two iterations I got a message saying system passed with no errors but testing was continuing on the third iteration. Does MemTest86 just keep running iteration after iteration until you stop it? Thanks.One word answer: Yes.
The possibility of a memory ERROR coming after several iterations is very low.
Some say that five is good enough. You decide.MemTest runs 12 to 14 seperate tests...however each iteration is one full cycle of said tests...

And yes...it'll run til the User shuts it down.

In most cases 1 HOUR straight is sufficient.The older version does not boot-up to a configurable screen. It automatically starts running. It identified two CPU's which I assume reflects my dual quad processor. It wasn't clear to me that it was checking both CPU's because it indicated it was checking just one. I thought eventually it would start testing the second CPU but it did not even after a couple hours. So, with v4.3.7 and a dual quad processor, can I assume everything is ok if I have no errors after two hours of testing? Quote from: artbuc on OCTOBER 16, 2014, 01:41:41 AM

The older version does not boot-up to a configurable screen. It automatically starts running. It identified two CPU's which I assume reflects my dual quad processor. It wasn't clear to me that it was checking both CPU's because it indicated it was checking just one. I thought eventually it would start testing the second CPU but it did not even after a couple hours. So, with v4.3.7 and a dual quad processor, can I assume everything is ok if I have no errors after two hours of testing?