Well there's this:
I don't understand why some people are in denial of Cell's ability to wreck the solar system. Let's look at the most common questions posited by those that think Cell was flashing its bravado.
I. How exactly would Cell's Kamehameha blow the solar system away?
Ultimate Budoten suggests the beam would strike the Sun and wreak havoc. What other examples do we have of Kamehamehas being fired at stars? Just that filler episode where Goku fires one at an unknown size to propel himself to safety. That tells us if a beam isn't strong enough to damage a star, it will effectively do nothing. Perhaps it may cause some solar flares that would fry nearby planets, but that's speculation. If guidebooks, filler and various games aren't good enough, let's take a look at if Jupiter crashed into the Sun.
The Sun clearly wouldn't be destroyed, but the Earth would be toasted. Assuming Jupiter was teleported to the chromosphere, seeing that its 88–92% hydrogen composition would hinder it otherwise, the energy released would cook the inner rock planets. Jupiter's mass is 1.898E27 kg. The escape velocity for an object at the Sun's surface is 617.553 km/s. Using K = 1/2 mv², we get 3.6192175071074E38 joules. The Earth's sky would be billions of times brighter than what it is now (if someone wants to do the math for this, it'd be appreciated). That's thousands of times less than a one megaton nuclear bomb's energy going off in a 50 foot radius (which as a whole should only release around 4.18E15 joules). The Sun may not be destroyed, but there's a good chance there'd be a nasty blemish on its surface along with the probability of disturbing its fusion.
I also found an interesting tidbit on if Jupiter suddenly turned into a thermonuclear bomb:
So if we presume Vegeta, whose battle power is roughly 18,000, could turn the surface of the Earth into a molten mess, then what about Jupiter? Well it's a gas giant, so who knows how it would react with ki, but let's assume there wouldn't be much different. It's 317.8 times more massive than the Earth, so 317.8 * 18,000 = 5,720,400. If someone were to object and say mass is irrelevant (I don't know why, but I've seen this), Jupiter has an equatorial radius 11.2 times larger than Earth's. 11.2 * 18,000 = 201,600. No matter how you slice it, Freeza would obliterate Jupiter with relative ease.
If Freeza can annihilate Jupiter, what's to stop him from pumping the Sun with enough death roids to fry the solar system? Okay, maybe that's not exactly the same thing as blowing up or "busting" it. So let's look at its size. To avoid debates, we'll say the solar system ends at the aphelion of Eris (97.651 AU, 9.07722754E9 miles, 1.46083817E10 km). Gohan's Kamehameha died out probably around where the Moon would be (384,400 km), or just a bit farther. So Cell's Kamehameha would have to cause enough devastation that it would, in some way (explosive energy), travel 38,003.07 times farther. A supernova would accomplish something like this, so I would have to go with Ultimate Budoten's depiction. Could the beam strike the Earth in such a way that it's so extreme as to engulf the solar system? Possibly.
II. Gohan's Kamehameha died out nowhere near the Sun.
This is true, however... many weaker beams have made it farther than that mark, such as Piccolo's to destroy the Moon and that one Freeza deflected into space. There's always the chance the beam went against the Earth's rotation, combined with losing even more energy on Cell's beam and Cell itself. Not to mention it was only killed because of a distraction, meaning if Gohan had released that amount of energy when Cell was pushing moments prior, it likely wouldn't've done much. Also factor in Gohan's beam had been charged for less time, with less effort throughout the struggle.
III. Pure Boo's 'Planet Buster' didn't destroy the solar system, so why would Cell's?
Freeza fired blasts that created incredible fissures that went on for miles along Namekian soil. Semi-Perfect Cell fired a number of blasts that only destroyed tiny islands. Vegeta fired a volley of blasts at Cell on three separate occasions, where the landscape remained virtually unharmed. This is irrefutable proof that there's an inconsistency amongst attacks. Now, this isn't necessarily a bad thing. Blasts and beams could simply be affected by what they are therein (i.e. what type of attack they are). Pure Boo's attack may not be the type of attack that's meant to do anything besides destroy planets. It may be overkill, but it simply may not be the type of attack to create an explosion equivalent to 1.46083817E10 kilometers. Now what if Pure Boo threw this at the Sun? Perhaps there would be a good chance that the solar system would indeed 'bust'.
Most Dragon Ball fans are incapable of making a logically sound argument.