Ok some hard facts for the ST guys from the CREATORS and INTELLECTUAL PROPERTY OWNERS of your universe.
Power output from a phaser bank for a sovereign class starship from the feds = 5.75MW as stated by the universe OWNERS! There are 15 of these. For a total output of 86.25MW. Or about 1/17th the output of a modern day 1500MW nuclear power plant. Photon torpedos with a yield of 64MT or 12MT larger than the most powerful nuclear device already detonated by man at 52MT. This is startin to look bleak.
Now for 40K vs. Star wars. I will compare the differences between the Imperium of Man and the Galactic Empire at its Hieght.
Alright time for some real world stats provided by Lucas Arts and Sir Isaac Newton.
Star destroyer. 8MT per turbolaser blast (lucas arts) multiplied by 60 turbolasers on an class 1 Imperial SD. A total output of 8 x 60 = 480MT / salvo. That's pretty devastating. (for the lols the enterprise e only emits 5.75MW per phaser bank).
First, Nova cannon. Bore is 50m. Fires its round at .95c or 95% the speed of light. Most battleships rounds (in real life) are 20 times longer than the bore of their gun.
So 50m x 20 = 1000m or 1 km (that's okay a nova cannon is 3.5 km long and the cruisers that carry them are 3.5 km long. Larger vessels carry them as well.
Volume of a cylinder 50m in diameter by 1000m long. V = (pie/4) x d(squared) x length. V= (3.14/4) x 50m(sq) x 1000m. V = .7854 x 2500m(sq.) x 1000m = 1 963 500 cu meters. Or in km 1.964 cu kilometers.
Mass = density per cubic meter x cubic meters = 7850kg/cu. m x 1 963 500cu. m = 1.54 x 10 to 10th or 15 400 000 000kg. I used the density of steel although the round is loaded with plasma warheads which are likely lighter than steel but the adamantium casing is far far far heavier. So say a wash (although I may be understating by quite a margin).
95% speed of c = 186 000 mi/s x .95 = 176 700mi/s. or 282 720km/s or 282 720 000m/s.
E(kinetic) = 0.5 x mass x velocity(sq.) = 0.5 x 15 400 000 000kg x 282 720 000m/s (sq.). = 6.155x10 to the 26th Joules! Or 615 500 000 000 000 000 000 000 000 Joules. Or 615 yotta-joules.
One tonne of TNT = 4.184GJ or 4 184 000 000 Joules. So 615 500 000 000 000 000 000 000 000 / 4 184 000 000 = 1.47 x 10 to the 17th tonnes of TNT. Or 147 000 000 000 000 000 tonnes. Or 147 peta-tonnes.
Now the blast of this round is much worse and takes out an approx. blast radius of 3500km. The plasma warheads are far worse than the kinetic energy but I remember a GW fluff (Which I can't recall) saying it was 2.5 times stronger than the kinetic energy of the round.
So. 147 petta-tonnes x 2.5 = 367.5 + 147 = 514.5 peta-tonnes. Per shot. Every 30 minutes.
An Imperium cruiser can soak 2 rounds resulting in destruction, that's right, 2 of these rounds! So a durability of lets say 1 exa-tonne but really its 1.029 exa-tonnes.
Star destroyer fires 480MT / volley. So in tonnes 1 029 000 000 000 000 000 / 480 000 000 = 2 143 750 000 volleys from a single SD to destroy a cruiser. Said cruisers that conservatively number in the hundreds of thousands for the Imperium of Man.
Lets throw all 35 000 SD of the Imperial fleet at that one cruiser! So 2 143 750 000 volleys / 35 000 SD = 61 250 entire fleet volleys! This means the ENTIRE Imperial fleet has to fire 61 250 volleys to destroy this cruiser!
Say they can fire every 5 seconds. 60 / 5 = 12 volleys / min. So 61 250 volleys / 12 volleys/min. = 5104.166667 minutes / 60 minutes per hour = 85.06944445 hours / 24 hours/day = 3.545 days. Of constant firing with no losses.
Now 8MT turbolasers are a threat to capital ships in SW. So the nova cannon itself will shred them, and the broadside of a cruiser is a low tera-tonne yield event which also shreds them. Now we can name the flagship of this campaign "The Shredder".
One IOM cruiser could wrap all of the empires SD's. At it's height. A SD has 60 heavy guns, an IOM cruiser has 3000+.
So know that we have official numbers from star wars that cannot be disputed as the BELONG TO THE INTELLECTUAL PROPERTY OWNERS AND THEY OVERIDE EVERY FANBOYS BASELESS STATEMENT REGARDING THOSE STATS, well its a wrap. IOM for the curbstomping.
The empire is outnumbered, outgunned, and outlasted in all categories. That nova cannon can slag DS II, one shot! Psykers will demolish the force users, and Alpha+ class can destroy planets, instantly with a thought. A lasgun will punch basketball holes in unarmored flesh, an unarmored blaster wound is survivable as seen with Leia on Endor's Century Moon. The God Emperor banishes souls from all time and existence as if they were never there. Sorry Palp's and Kun. IOM FTW.