nForce2 PCI Bandwidth

ugh

Platinum Member
Feb 6, 2000
2,563
0
0
Hi all,

My friend's been saying/complaining that the nForce2 mobo has ~22Mb (??) of bandwidth compared to the rest of the mobos which is around 100Mb. Any idea where to find this info? I've read various nForce2 mobo reviews but still can't get any info in them. He's thinking of getting an nForce2 mobo, but since he uses high-end vid capture card (Pinnacle), he's not touching the nForce2 by a long shot.

Any ideas?

TIA.
 

mechBgon

Super Moderator<br>Elite Member
Oct 31, 1999
30,699
1
0
I think he's remembering a bug that some boards had back in the days of the original nForce, where IDE write speeds were strangely low. BIOS updates fixed that on everyone's boards except (I think) Microstar's.

I have an Adaptec 19160 SCSI card and a single Cheetah X15-36LP hard drive here and can assure you the PCI bandwidth is very high. Using Adaptec SCSIBench to measure same-sector reads at large blocksizes, I get over 120Mb/sec sustained throughput from the card to the motherboard, and this is just with an older nForce 220D board. I'll have my shiny new nForce2 (EPoX 8RDA+) on Wednesday, it looks like, and be able to confirm how well it does.

With nForce and nForce2, the southbridge is linked to the northbridge by a full-duplex 400Mb/sec Hypertransport link (that's 400 each way). Obviously, even with a maxed PCI bus (133Mb/sec), there's still a lot of bandwidth left over for the other stuff built into the southbridge, which includes Firewire on the MCP-T southbridges. So I'd encourage him to give it a try. The EPoX 8RDA+ is only $105 plus s/h at mwave.com, and if he doesn't find it satisfactory, I'm sure he can sell it quite easily around here :D Hope my ramblings were of some help... :)

By the way, if he does pick one up, I got some tips from Insane3D for selecting the WHQL-certified driver at installation time, which is going to be the better choice for users doing intensive IDE work such as DAE or CD/DVD recording:

When you install the Nvidia 2.0 driver pack, it will ask you if you want to use the Performance "SW" drivers. If you reply no, it installs the normal WHQL ones.

 

SpideyCU

Golden Member
Nov 17, 2000
1,402
0
0
Yeah, that whole "22 MB/sec" bit was either a mistake on his part, or someone gave him some faulty info. I'd be curious to know where he got this "information".
 

ugh

Platinum Member
Feb 6, 2000
2,563
0
0
Thanks for the info mechBgon. Do let me know on the performance of the nForce2 in terms of PCI bandwidth.

Spidey: I'm not sure where he got his info from, but I'm gonna find out tonite.

BTW, is the bandwidth in bits or bytes? :)
 

mechBgon

Super Moderator<br>Elite Member
Oct 31, 1999
30,699
1
0
Bytes, and I'll post my update here tomorrow afternoon-ish, once I get the new board installed and get Windows reinstalled. :)
 

ugh

Platinum Member
Feb 6, 2000
2,563
0
0
Thanks for clearing that up ;) Will be waiting for yer results.

BTW, have you heard of any recurrence of the low bandwidth problem in nForce2 mobos?
 

mechBgon

Super Moderator<br>Elite Member
Oct 31, 1999
30,699
1
0
I posted my results in this thread. Basically, nForce2 and nForce classic both seem to have the same (high) PCI performance. I tried transfers between an UltraATA 66 PCI IDE controller and a SCSI PCI controller, I tried benchmarking on both at once, it all adds up to 120Mb/sec of PCI bandwidth. Looks like a keeper :D