the 5.1m number is the PS4+XB1 (by game estimates of sales).

MVC estimates 5.4m sales of PS4+XB1.

If the PS4 sold 5.4m out of 5.4m sales of both PS4+XB1, that would mean XB1 sold 0 units.

Thats not real. Thats the highest possible amount of PS4s there could be.... obviously thats not how many there are, because there are XB1 sales in the UK.

So.... PS4 sales in the UK are under 5.4m.

However you also have people saying PS4 is over 3m.

Theoretically that means the Xbox *could* be around 2.4m, in the UK.

Its probably lower than that, due to either estimates of combined sales being to high, or the "over 3m" PS4s, could mean anything (3.1 or 3.2 ect).

the 5.4ml is possible since GAME is only about 95% of the market in the UK. I could see the ps4 at 3ml.

Thats not a "seeing" thats a confirmed I think.

Yep.

You cant really draw any conclusions from this.

For now all we can get from this is:

XB1 is under 2.4m in the UK, and the PS4 is somewhere over 3m.

This thread is a mess.

DEFINITIONS

GAME: A UK retailer who specialises in selling Video Game hardware and software (Think GameStop in USA)

MCV: A trade magazine that specialises in Video Games news

GfK: A market research firm who track 90 to 95% of game sales in the UK.

THE ARTICLE

1. PlayStation announced record sales in the UK and confirmed that more than 3 million PS4's have been sold in the UK as of January.

2. MCV heard reports from retailers that the PS4 & XB1 install base was over 5.4 million at the same time. The retailers who provided MCV with this number have access to GfK figures.

3. GAME says that the PS4&XB1 install base was over 5.1 million as of January 23rd 2016. GAME quote IHS, GfK & IDG as the sources for these numbers.



Why the discrepancy?

GfK track about 90%-95% or so of all stores in the UK. It would seem to me that GAME are using raw GfK figures in their comparison whereas the retailers upweighted the number before telling MCV. This is also what an employee at MCV told me when I asked the same question. 

What are the conclusions?

PS4 has sold over 3 million in January
Install base is over 5.1 million according to GfK raw figures. (as of Jan 23rd 2016)
Could be over 5.4 million if you account for stores that GfK do not track.

We do not know Xbox figures.

(Someone add this to the OP please)

I might have worded it wrong but i belive that the ps4 is over 3ml

You dont need to "believe" anything, like ZhugeEX wrote, playstation confirmed sales over 3ml.

Its over 3m.

Yeah, you're missing something. That VGC figure you took is from 5th March. The 5.4m figure is from 23rd January.