Honest question about cartridge vs. turntable performance.


I’ve been a vinyl lover for a few years now and I have an ortofon black cartridge setup with an mmf 5.1 turntable with acrylic platter and speed controller. My question to all the vinyl audiophiles out there is this. How much difference does a turntable really make compared to the cartridge? Will I hear a significant difference if I upgraded my turntable and kept the same cartridge? Isn’t the cartridge 90%+ of the sound from a vinyl setup? Thank you guys in advance for an honest discussion on this topic. 
tubelvr1
I meant to say “Unless” rather than “So” in the first sentence of last paragraph.
Thank you everyone for all your responses. My budget is limited to no more than 2k for the upgrade therefore I posed the question. I was wondering if I could just upgrade the cartridge and phone-preamp for best “bang for the buck” upgrade. I guess my main question is this: if there is surface noise when playing back vinyl (even after thorough cleaning) isn’t upgrading the table a nearly useless endeavor beyond a certain point since the noise floor improvement from a better table will never be realized? Am I being accurate in my assessment? 

 if there is surface noise when playing back vinyl (even after thorough cleaning) isn’t upgrading the table a nearly useless endeavor beyond a certain point since the noise floor improvement from a better table will never be realized?
not necessarily. you would have to do some testing to refine what is causing the noise. surface noise might be a few different things. the best approach is to first eliminate the obvious things before you start thinking about the platter or motor.

ideally you have a few Lp's and could hear them on a known properly performing turntable to get a reference for how they should sound. maybe even take them to a local hifi shop and ask them to play a short passage to find out (assuming they have a turntable).

or buy a new record that you confidently feel is likely quiet and properly pressed.

1--this noise could be as simple as some sort of gunk adhering to your stylus. heat from friction in the groove can cause that gunk to stick strongly. read up on proper cleaning methods for your cartridge.

2---could be the vinyl itself maybe with groove damage. or just a terrible pressing.

3---could be a loose cartridge mounting, or loose arm mounting.

4.---obvious noise from the platter or motor is unusual. typically you might hear some noise during very quiet passages, or maybe some 'sour' discontinuity during horn or piano sustains. but both of those things are lower level type noise, not in your face. 
With groove damage, the issue is not obvious in most cases by looking at the LP. Last night, I put on what looked like a Mint condition Direct to Disc, the groove noise was annoying from the lead in groove on the first side to the lead out groove on the last. 
Many LP's look to be in great condition, but once on the table, they show off their true condition. I think in the case of this particular LP, the previous owner(s) had used a cartridge that was worn or otherwise damaged, as such after just probably one play, the LP was damaged. The fact that the LP was a Direct Disc would lead me to question whether the album had been also played back on gear that was unable to really track this album..thereby resulting in the damage.
@millercarbon  I totally disagree concerning the demotion of digital sound to analog sound.  They are different but not incompatibly inferior to one another.  My CD reproduction has the same (or better) PRAT, tonality and dynamics as my analog reproduction.  The analog has the extra breath of life.  Analog can also have many problems from the vinyl pressing.  The biggest difference is mastering and either one can have great or not so great mastering.  I used to do all my semi-professional recordings on R2R, then DAT, now on a digital recorder.  I know the difference is there but there exists an advantage to each type.

As to turntable/arm/phone stage/cartridge-My modded $1100 1989 purchase of an SME IV arm sold last year new retail at $4600.  My phono stage would cost over $10K today (I paid $1500 20 years ago).  The Audio Interface SUT is now again available directly from Jensen transformers at the same price.  My turntable is a VPI TNT VI and would cost at least as much as I paid to replace it, if not more.  Only the cartridge is expendable and I chose to pay $2K 14 years ago.  Now I'm looking at $3K to $3.5K.  I am not willing to spend more even though I can afford a more expensive cartridge.  I like my tonearm because it is so durable and VTA is not as critical per LP as some other high end arms.