
LOL, to seriously say the Parhelia can compete with GF4 is a laugh. I can pick some benchmarks for you showing the 4200 beating the 4600 when both are at defaults etc etc, it certainly isn't representative of the whole picture. Check this out.
http://firingsquad.gamers.com/hardware/parhelia/
In 3Dmark2001, P512 is behind the 4600 (only other card) in ALL parts of benchmark inc 1600x1200x32, 4600 50% faster.
In Q3A noAA, the 4600 miles ahead, and gap widens (not narrows) as res increases.
In Q3A AA, 4600 uses worst perf 4xAA and still beats P512 FxAA until 1280 where about even, and 1600 both unplayable.
In JK2 noAA & AA, 4600 still whips the P512 and still has a narrow lead all the way to 1600x1200x32xAA although unplayable.
http://www.anandtech.com/video/showdoc.html?i=1647
UT2003 1600x1200-HI DETAIL, P512 slower than R8500 & 0.5FPS faster than GF3TI500, 4200 is 25% faster!
UT2003 1600x1200-MID DETAIL, P512 EVEN slower, now 20% slower than GF3TI500!
In the more demanding Asbestos benchmark things are even worse! GF3TI500 is 20% faster 16x12-HI & MID slower than GF2ultra!
http://www.tech-report.com/reviews/2002q2/parhelia/index.x?pg=1
CodeCreatures, both R8500 & 4600 squirt pee on the P512 in all res up to 1600x1200x32.
SerSam2, both R8500 & 4600 beat it again right up to 1600x1200x32.
3Dmark2001, 8500 & 4600 win again.
AA, P512 takes huge perf hit when switching from noAA to 4xAA esp compared to even the 8500, FxAA does cost little perf tho.
Aniso, P512 can't do any other than 2xAni but should be able to do 8xAni with updated drivers, what perf hit tho?
http://www17.tomshardware.com/graphic/02q2/020625/index.html
Giants, again all the way up to 1600x1200x32 the 8500 & 4600 easily laugh off the P512.
MaxPayne, the P512 can now equal the 8500, but 4600 is more than 60% faster than both in all res up to 1600x1200x32.
Aquanox, same as MaxPayne, can equal the 8500 but 4600 streets ahead.
Commanche4, At last the P512 beats the 8500 in all res, albeit marginal in 1600x1200x32, at which the 4600 is 200% perf!
DungeonSiege, Again P512 just beats the 8500 but never nears the 4600.
JK2, P512 is miles behind both 8500 and 4600 in ALL res up to 1600x1200x32. Both more than 60% faster at 1600x1200x32!
Q3A, P512 no where near either card AGAIN! At 1600x1200x32 4600 is 200% perf of P512 AGAIN!
3Dmark2001, Once again both cards are flying ahead of P512. Again 1600x1200x32 shows the 4600 more than 60% faster.
Q3A Aniso, not only does 4600 look better but is much faster and takes less of a hit in ALL res.
MaxPayne, Aniso likes P512 most but 4600 still a LOT faster.
AA, FxAA not work in all games or conditions so P512 has to use 4xAA which it does very slow, big perf hit.
MaxPayne, AA, 4600 QxAA easily beats the P512 FxAA and even the 4600 4xAA is about even with P512 FxAA, P512 4xAA VERY slow.
Q3A AA, Same story as MaxPayne but now just about playable at 1280x1024x32, 4600 QxAA double P512 FxAA.
Q3A AA&Aniso, 4600 QxAA (not need for 4xAA when using Aniso) actually faster than P512 without anything enabled!
MaxPayne AA&Aniso, pretty much the same as Q3A.

Please excuse my shorthand but I believe most people will still understand it. You may think that the 4600 is an unfair comparison but rem that is where the P512's price point places it. The Radeon8500 is about a third the cost and beats the P512 almost every time too!