/ Sign-up
Your question

P45 vs X48

  • Chipsets
  • Motherboards
  • Product
Last response: in Motherboards
July 9, 2009 8:48:29 PM

I had considered this in the chipset subform, but I wasn't entirely sure, so I figured this would also work. Feel free to yell at me if it does in fact belong in that sub-dwelling. It could actually go in 'homebuilt systems' too, really, but I digress.

I have recently purchased a whole buncha parts for my new computer build, mostly everything except a few things I already had lying round. I'll give you a brief run-down for reference sake ..

- Q6600 processor (planning on overclocking)
- XFX 4890 XXX video card
- HAF 932 case
- Thermalright Ultra 120 HSF
- 4 GB Patriot Viper Extreme Performance DDR2-800 + 4 GB OCZ DDR2-800 (mixing RAM, lovely hardware lottery)
- Corsair TX850 PSU
- Asus Xonar DX 7.1 sound card
- Sunbeam Rheobus fan controller
- OCZ XTC RAM cooler
- P5Q pro motherboard
- LG 24" (1920x1200 res)

Now, the issue at hand is the P45 chipset on the P5Q pro. Although a lovely, stable chipset, it has the unfortunate quality of only running 8x/8x in Crossfire mode. Unfortunately for me, I was also planning on adding another 4890 card in about a month or so. However, the single card will of course run at full 16x.

The X48 boards, on the other hand, run with full 16x/16x bandwith in crossfire, and therefore won't 'bottleneck' high-end cards, to speak. If you refer to the tweaktown reviews/benchmarks ( ), you'll see a significant difference between the two chipsets. Now, that particular benchmark is Crysis, only one game, but demonstrates the performance difference in a pretty stressful environment.

Other benchmarks comparisons available at however, demonstrate smaller performance drops with the P45 chipset. Although, it should be noted that that particular benchmark is Crysis in DX9/no AA, so less demanding than the previous benchmark.

This is mostly an advice question: should I consider returning my P5Q pro (order hasn't arrived, yet) in favor of an Asus Rampage Formula X48 board, assuming I go Crossfire (2 4890s)?

Here's a link to the X48 board:

And a link to the P45 board (already purchased, can return):

Mind you, the X48 board is also twice the sticker price of a P5Q pro, but considering the cost of 2 video cards for Crossfire and the P45 performance concerns, I'm thinking I should consider it.

Does anyone have any personal experience with P45 chipsets vs X48 chipsets with Crossfire?

Any advice is appreciated.

More about : p45 x48

a b V Motherboard
July 9, 2009 9:09:49 PM

the X48 board is also twice the sticker price of a P5Q pro

Exactly, double price is ridiculous. 8 x 8 bandwidth is more than adequate for most useage/games should you go Crossfire. Of course, the bandwidth is the same when using a single card. The X48 is a higher binned chip, but the P45 Oc's very well even if benchmark scores are your measure of greatness. Nice graph. The people who compiled it may not be able to tell the difference in the setups if they didn't know before hand. :)  Newegg has a few X48's for 'buyable' consideration when comparing to the P45. The top two lowest priced units may be worth the premium over a full featured P45 if that is what you are looking for price/performance.
Related resources
July 10, 2009 4:57:41 AM

Actually, that was rather helpful. It really doesn't seem to be much of an issue in that particular case. Actually, that almost completely contradicted what was put forward by Tweaktown.

My only issue is that that review used a 4870, obviously a good mid range/high-end card. Now, assuming I were to ever pop some new cards into that P5Q, the performance loss due to bandwidth (in Crossfire, though) would become even more of an issue. Assuming the new ATI cards (5000 series) are coming out in October, these would saturate an 8x bus even more, and considering I can't buy new hardware til next summer, there may be some major improvements.

I guess this comes down to future-proofing, really. The performance differences are minimal according to Toms, whom I trust more than Tweaktown. It's just a matter of future cards and the corresponding consequences.

Perhaps I should just consider the P45 platform a temporary, and consider moving up to X58/chipsets being released by summer of 2010 instead of investing rather heavily in this outdated platform.

Thoughts? Either way, I doubt I'll end up chocking up 320$ for a board that is old news, essentially. You can get X58 boards for that price, which is silly considering how 'old' it is.

I'm thinking a Q6600, pair of 4890s, P5Q pro, etc should be plenty fast for now..

a c 507 V Motherboard
July 10, 2009 12:57:49 PM

I'm thinking a Q6600, pair of 4890s, P5Q pro, etc should be plenty fast for now.
That's what I would do.