Sign in with
Sign up | Sign in
Your question

Performance impact of AM2 HyperTransport speed on AM3 cpus

Last response: in CPUs
Share
October 30, 2009 7:27:04 PM

Hello people;

I have a question about the preformance impact of HyperTransport speed upon modern AM3 cpus on an older AM2 mobo.
I have an AM2 mobo (without the +), model: MSI K9AG Neo2-Digital.

It has an AMD 690g chipset, and I currently use an Athlon 64 3800+ cpu, which is just fine, but I am trying to find out if upgrading the cpu could prolong the life of my system with a year or 2-3.
I have 2Gb of Ram, and Windows XP.
I am a casual gamer. (who does not care about resolution nor Anti-Aliasing etc.)

Now, my cpu-upgrade options are vast it seems. I checked on www.cpu-upgrade.com, because the website of MSI is not up-to-date for my mobo.
According to them, I could go for most, but not all Athlon x2, Athlon II or Phenom II (they show a specific list on their website).

But my mobo is an AM2 mobo with DDR2-800 and a maximum Hypertransport speed of 1Ghz (HT 2.0).
I have already learned that the performance hit of DDR2 is negligible for these new cpus (Athlon II, Phenom II),
but I have no idea about the impact of hypertransport speed.

Does anyone know if a 1Ghz HT2 link has a noticeable impact? (That is the maximum HT speed my mobo can give in HT 2.0 mode.)
Because of this, I am still hesitating between:
- a 2-core or a 4-core: HT limitations may be more of an issue for a 4-core, so could a fast 2-core be a better upgrade choice for an AM2 mobo?
- an athlon II or Phenom II: If HT speed is an issue, then maybe a cpu with a large cache system could be a better choice? So could a Phenom II x2 be a better choice than an Athlon II x2?

Actually, depending on the price and possible HT speed-issues, I am hesitating between:
- AMD Athlon II X2 240 (2,8Ghz) or a AMD Phenom II X2 500 (3Ghz)
- or any AMD Athlon II X4 or a Phenom II x3/x4.

I have no idea how to calculate HT bandwith, let alone how much of this which cpu needs.
So if HT could be an issue, I might as well buy a cheap Athlon x2 5050e or so, which will probably do for the next 2 years.

Thank you very much in advance;
Carl
a b à CPUs
November 1, 2009 5:32:08 AM

Athlon 64 X2 6000+ (3.1GHz) 89W
Is the best option you have....... or I guess 6400+
Do not go in for the Phenom II X2 or Athlon II X2 .
You will have bottlenecks, and that means a time or a delay time between the functioning of programs or even while copying from one disc to another, it'll all appear to go smooth for a few seconds and then stop for a minute and then get back to moving on and then again , so on and so forth.
You have to stick to something that has an FSB that is capable of less than or equal to the HT speed..... anything higher will cause a traffic jam....
Although you can get a higher processor and OC the HT a little but it ends up creating problems for the user......
I would still suggest , if you don't plan to change your Mobo for the next two years , go for the 6000+ or 6400+ athon x2 series...... do not opt for the Athlon II or Phenom II......
Any of the new processors you chose from will give you good spped with the latest mobos having AM2+ or AM3 sockets.... and DDR3's to get the best deal.......
If you're upgrading just the CPU.... go for the 6000+ nothing is going to beat it......
Atleast not in that category of AM2s
a b à CPUs
November 1, 2009 5:34:27 AM

And sorry...... YES the IMPACT is more than noticeable......
The cheap ones are the best option right now. Save your money and you'll have enough in the next year to make a whole new AM3 state of the art system.....
Related resources
November 26, 2009 11:22:33 PM

I have a AM3 cpu in my AM2 mobo, its downclocks the HT cause thats wat your mobo can handle.
It doesn't affect performance one bit, well for gaming atleast.

My amd64 x2 4800+ brisbane, running with a small OC 2.5ghz > 2.7ghz was bottlenecking my GPU NV260gtx 216.

CSS stress tests showed me the bottleneck, how? easy, both cpu+gpu standard clocks @1280 1024 60hz.
Result 171.xx fps.

Gpu only, overclocked by 40 mhz
Result 173.xx fps

Cpu only, overclocked from 2.5 to 2.7ghz
Result 190.xx fps

Both overclocked = 191 fps.

Now rip out the amd 4800+ x2 and stuck in a shiny AMD Athlon II X2 Dual Core 250 3.00GHz (Socket AM3)
First updated my Bios to the latest rev, for my GA-M57SLI-S4 rev2 mobo.

Result 236.xx fps. WoW runs 10fps better MINIMUM fps, so it cost me 60uk pound for an extra 10fps MIN not Max, Minimum fps is more important these days than Maximum. Was well worth it for me :) 
November 26, 2009 11:32:13 PM

The reduction in hypertransport speed is not a deal breaker. I'm running a X2 7750 on my old AM2 board and performance is exactly where it should be. You'd be fine with any of the AM3 options you've posted.
May 20, 2010 7:27:47 PM

I put a phenom 2 945 in my GA-M57Sli4-S4 revision 1, updated with the F15D bios and it runs much better than my Athlon 64bit 3200. (yes the m57 i have is an AM2 socket but gigabyte were excellent in updating the bios on this old board, and AMD clever for making the sockets back/forward? compatable)

Super fast opening and closing things in windows xp 32bit. Fallout 3 runs much smoother too (nvidia 7600 gt), and suprise suprise i can run multiple virus scans, internet tv, and very large word documents full of diagrams and formulas along side powerpoint.

The only thing that pushed the CPU to 100% was converting FLAC files to MP3. I havent noticed any bottlenecking, or struggling on the part of the processor...but i have limited experiance an i am bound to see an improvement in compariosn to the AMD 3600.

This processor is an excellent choice for me becuase I plan to upgrade to an AM3 motherboard and get a resonably priced graphics card ~£100 later in the year. Also I found the AMD 3600 too slow for what I needed the computer to do currently.

Good luck in your hunt, I can see it may be a benift to buy a cheep processor ~£50/60 and wait until you buy a motherboard that can handle the speedier processors, then shell out again for a good processor. I just went for the more expensive processor now because it takes me so bloody long to buy one thing, i dont want to have to brush up on my processors again for another 3 years!
a b à CPUs
July 27, 2010 12:10:18 PM

get yourself a Phenom 2 x2 550 for only $100! Then you will have yourself a really fast dual core and when u decide to get an am3 board just get 1 that can unlock the extra cores and there ya go u have a quad that will probably easily O.C to 3.8ghz! For your answer yes you will have a small bottleneck with your current board. however, I know from experience it will not be that noticeable. I used an am2 board with my phenom 965 and it ran like a champ!! good luck bro
!