Well, my experience is not the best when it comes to MSI boards and the first thing i think when i see the brand is : BAD CAPS!

Now i know that a lot of people like MSI and have no problems and they make good products etc. But most of the MSI products that came trough my house (and that's a lot) were dead.
Graphics cards and mostly p4 and AMD Athlon (xp) period motherboards all had bad caps or just didn't fire up.

I still see problems with caps in medion products that are not that old (core2duo) and these boards are made by MSI as well....

Having said all that, did you check the caps and do they at least look good?
I think a recap will solve a lot of your problems.

The processor seems to run on a lower fsb (533fsb) so it runs at 2,8 ghz. Running it at 800fsb gives you 3,4ghz.

The caps are in pristine shape on my board and yea every msi board ive ever had come through my repair shop had all been crap and none of them had bad caps they where brand new boards, ive never once had luck with them and the ones Ive had, had the weirdest problems with them.

I manged to get xp to install and it was working good, no when I got back from work I cannot get it to show picture it turns on, but no post. This is just the weirdest crap ever and ive tried multiple video cards and ram sticks, still no dice.

It shows the cpu running at 800FSB with my 3.4GHz, but it still shows my 3.4 @ 2.80

Another thing I would like to point out is why the hell does this board have 64 Bit drivers. From digging around a little online ive been hearing that the socket 478 3.4 was supposed to be a 64 bit processor, but intel never fully implemented it. When looking at my 64 bit .exe files on a 32 bit computer it does not show the .exe icon cause the cpu cannot read it obviously, but with this motherboard (if I can get the damn thing to fire) it shows those 64 bit .exe icons, weird!

If it is a prescott it might be a version that does support 64bit?

wiki says:

Intel 64: supported by F-series, 5x1, 517, 524 and few OEM models in E-series (SL7QB, SL7Q8)

sl7q8 is a 3,4ghz s478 prescott. Anyway, keep the cpu and ditch the board is my advice 🤣 There are a lot of boards that can be had cheap so i wouldn't bother to put any more time in it.
I have an Asus P4C800 and it works great.

Got it to fire up again after leaving it sit with coin battery out, popped in the 3.4 prescott, bios shows 2.8ghz and windows xp shows 3.4. Kinda wondering if I should recap the board cause the bios boot screen logo is all glitched looking even inside of the bios that grey underlay box thats under the red box doesn't look right either.

To me it seems like a recap is in order I have had boards do similar things and the caps looked perfect but after pulling the caps and checking them they were all waaaayyy out of spec and a full recap saved them all.