Intel Q9400 vs Q9550

armadillo_me · 22 Oct 2009 at 23:38

is there much between them? The best price diference is around £70...
Overclocking them what would be a decent mark in both? Thankx (sorry a newbe here)

setter · 22 Oct 2009 at 23:43

The q9400 only features 4mb cache compared to the 12mb on the q9550, also the q9550 has a higher stock clockspeed at 2.83ghz, 8.5x multiplier as opposed to 2.66ghz with an 8x multi on the q9400, the q9550 will be easier to clock higher.

armadillo_me · 22 Oct 2009 at 23:53

Thank you Setter, i already asked a similar question in moterboard forum but which motherboard for a Q9550?

setter · 23 Oct 2009 at 00:03

I used an asus p5q deluxe p45, had an easy 3.8ghz out of a q9550. The p5q pro/p5qE are also pretty good boards at a lower price. Gigabyte also do some very good p45 boards but im not that familiar with them having never owned one.

armadillo_me · 23 Oct 2009 at 00:08

Thank you Setter!

marscay · 23 Oct 2009 at 04:35

The Gigabyte EP45-UD3P is probably the best clocking P45 board but pretty hard to find now, just sold mine last week actually and i think there is another on the MM.

The Asus are very good too and if you want to get near 4ghz on a 9400 you'll need a top top board which can do high FSB.

uk_unbeliever · 23 Oct 2009 at 18:28

slightly related, I've got a p43 board with a fsb wall around 415ish. If I upgraded to a quad in the future would the higher multiplier on a q6700 make it a better all round buy than a q9550? Am I missing something when thinking that the higher multi will enable higher clocks (generally), and then its just a balance against the probable higher temps and less cache (but less £ also) v higher clock? someone let me know if i'm being thick here with regards to these 2 cpus

toon_mad · 24 Oct 2009 at 00:13

im currently up to 4ghz on my setup within a day, i reckon i can hit more pretty easily

armadillo_me · 26 Oct 2009 at 13:00

Thank you, after some thought, and some advice i will go with the i7 920 although amd phenom 955 looks interesting too...this new choice is more expensive than the first option (775 socket) but more "future proof"...

I7 920 cpu
Gigabyte EX58-UD3R
Sapphire Radeon HD4650 512MB
Barracuda 7200 500GB Sata
LG DVDRW 22X INT SATA
another few Hd
Corsair (TR3X6G1333C9)6GB (3x2GB) DDR3 1333MHz XMS3 Memory CL9
Windows 7

A few questions:
-is a 500w psu enough?
-what means in the memory ref CL9 (9-9-9-24)?
-is it the right memory?

Thanks

gurusan · 26 Oct 2009 at 16:19

setter said:
The q9400 only features 4mb cache compared to the 12mb on the q9550, also the q9550 has a higher stock clockspeed at 2.83ghz, 8.5x multiplier as opposed to 2.66ghz with an 8x multi on the q9400, the q9550 will be easier to clock higher.

Actually the Q9400 has 6mb cache, it's the Q8xxx series that have 4mb.

Greebo · 26 Oct 2009 at 16:32

As said, the differences are cache which means clock per clock the q9550 will out perform the q9400 in certain programs.

The multiplier makes a big difference to overclocking potential at the extremes though.

to get 4ghz a q9550 only needs a fsb of 470 whereas the q9400 will need 500.

As a person who used to have an x48 mobo which was fsb limited to 444Mhz with 45nm quads I would have only got 3774Mhz and 3552Mhz respectively and even with my q9650 I was limited to 3996Mhz.

Mobo's capable of 500+ fsb stable are few and far between but the ep45-ud3p certainly are (see sig).

Of course if you are not planning on overclocking to the extreme then assuming that you can get both of them to the same speed there will not be much real world difference.

EsaT · 26 Oct 2009 at 20:03

Greebo said:
As said, the differences are cache which means clock per clock the q9550 will out perform the q9400 in certain programs.

Games love big L2:
http://www.xbitlabs.com/articles/cpu/display/amd-phenom-ii-x4_7.html#sect0

Rroff · 26 Oct 2009 at 20:13

Greebo said:
Mobo's capable of 500+ fsb stable are few and far between but the ep45-ud3p certainly are (see sig).

Most of the higher model gigabyte P35 boards could run 500 FSB stable even with 65nm quads - tho you'd have to back the multi down unless you had a really good quad to get there

mine tops out at 516 stable.

gurusan · 26 Oct 2009 at 21:16

EsaT said:
Games love big L2:
http://www.xbitlabs.com/articles/cpu/display/amd-phenom-ii-x4_7.html#sect0

If you game at 1280x1024 then maybe a bit......

Ryan-3 · 26 Oct 2009 at 21:26

A 500W PSU may be pushing it under heavy loads (i would say anyway)

Go for 600/650W to be extra sure

Greebo · 27 Oct 2009 at 09:02

Rroff said:
Most of the higher model gigabyte P35 boards could run 500 FSB stable even with 65nm quads - tho you'd have to back the multi down unless you had a really good quad to get there mine tops out at 516 stable.

I agree but the list is small and it's hit and miss with mobo's as to whether the board can handle 500 fsb.

Some of the Asus mobo's are also good for 500 fsb.

I was just pointing out that it is a factor (especially if you already own a mobo) as to which cpu you buy.

I was gutted when I had to sell my watercooled mobo just because of it's 444fsb limit and I wasn't getting the most out of my q9650.

In fact the board I bought to replace it cost £70 less yet will run 512 fsb 24/7 and will actaully do 544 fsb but the cpu needs too much voltage for that to be a 24/7 clock

gurusan · 27 Oct 2009 at 11:11

P35's were fine for 65nm but really are not that great with 45nm quads.

I have a P45C-UD3R on the way from the states, looking forward to clocking one of these legendary UD3 series boards. I'm hoping for a 500x9 4.5GHz clock on my E8400 with 2GHz CL8 ddr3...and perhaps December or January a 4.25GHz or higher Q9550

EsaT · 27 Oct 2009 at 17:09

Ryan-3 said:
A 500W PSU may be pushing it under heavy loads (i would say anyway)

For graphics card mentioned by armadillo good 300W PSU would be enough.

gurusan said:
If you game at 1280x1024 then maybe a bit......

Effect of CPU doesn't show if graphics card is "sweating blood"...
Or do you want to just measure that graphics card doesn't have the muscle for resolution/settings?

armadillo_me · 27 Oct 2009 at 17:19

EsaT said:
For graphics card mentioned by armadillo good 300W PSU would be enough.

Thanks that's what i thought!

setter · 27 Oct 2009 at 17:34

gurusan said:
and perhaps December or January a 4.25GHz or higher Q9550

Look forward to seeing that, ive seen a few on xs do 4.2-4.4ghz using the udp series boards, they seem to clock the 45nm quads just that little bit more than the asus equivalents.