[justlurking]

That sounds like a video problem (i.e. hardware), not a malware (software) problem.

[EQAndyBuzz]

Sounds like a bad heat sink. Dell has had a lot of those. However, if you think it is Maleware, either Maleware Bytes or Kaspersky are the best tools for it.

[Paladin2]

I tend to agree with the h/w issue as a quick diagnosis.

I'd try booting the unit with something like knoppix to see if the problem persists.

[mmichaels1970]

That sounds like a video problem (i.e. hardware), not a malware (software) problem.

I agree.

Try booting into safe mode. Restart and press F8 a couple of times during the boot process. Select "safe mode". This will default your video adapter to basic VGA settings. If you are still seeing the rainbow, I'd bet you have a video problem.

The fact that you are seeing it on the startup screen is a big sign that the issue is video card/hardware related. Malware, except for some extreme "root-kit" related instances will usually take hold after you log into your computer.

If you are REALLY convinced it is malware, you could try downloading combofix from bleepingcomputer.com. If you have some sort of malware that is infecting you before windows starts, you're going to need something like combofix. Combofix isn't for the feint of heart, but it is designed to rip out rootkit viruses.

[editor-surveyor]

No, this is clearly intelligent information, not malfunction.

I realize that AC leaking into the power would generate horizontal bars, but it wouldn’t make that concentric, changing and complex graphic that appears in the upper left corner of only the startup screen.