SAPPHIRE 100270SR Radeon HD 4850 X2 in pcie2.0 16x

Forum for all the AMD (Previously ATI) video cards from the past, present and future!
Post Reply
redkal13
Legit User
Legit User
Posts: 7
Joined: Wed Feb 17, 2010 2:39 pm

SAPPHIRE 100270SR Radeon HD 4850 X2 in pcie2.0 16x

Post by redkal13 » Thu Feb 18, 2010 6:55 am

I am planning to build my first pc and i got a whole list of parts. Now i noticed that the mobo i was gonna get has pciex16 lanes that operate at x8. Im not sure the board even supports crossfire... this one... http://www.newegg.com/Product/Product.a ... 6813186150 FOXCONN A7DA-S. So i looked around and the SAPPHIRE PURE CrossFireX 790GX caught my attention. Its got 2 pciex16 lanes that run at x8, but they got a switch card that u put into the bottom pciex16 lane and it makes the top one function as a x16 lane. So im guessing that if i put in that switch card and put in the vidcard thats a 4850x2 ill be runnin both cores at x16 right? Or am i just wrong and the 4850x2 runs at x16 on any board?

heres a review of that board.... http://www.overclockersclub.com/reviews/sapp_790gx/

User avatar
skier
Moderator
Moderator
Posts: 4450
Joined: Mon Mar 26, 2007 3:29 pm
Location: Maine
Contact:

Re: SAPPHIRE 100270SR Radeon HD 4850 X2 in pcie2.0 16x

Post by skier » Thu Feb 18, 2010 9:18 am

the 4850X2 should run at x16 if the one PCIe slot runs at that(95% the case) the only time it would be restricted is if you are running Crossfire in a multi-Card setup, as in dual 4850X2's in which most boards would force either 16/8 or 8/8 lane operation. and its not that the cores are at x16, its the bandwidth between the card and the rest of the system (CPU/chipset primarily)

so as long as you are only running a card in one physical PCIe slot you'll be running at PCIe x16 speed, it's when you add another physical card that it commonly gets limited to x8 operation
-Austin
Image
Screamin' BCLK: Image
775 System (Overclocking Platform): Q8400/Q8300/E8400/E7400/E7500 - GA-EP45-UD3R v1.1 - 4GB (2x2) OCZ Reaper HPC DDR2 1066 CL5 2.1v Corsair TX-750w
Gamer: Asrock Z77 Extreme4, i7 3770K @4.6GHz, ThermalTake Armor A90 modded, 2x4GB GSKILL RipjawsX DDR3 2133 CL9, Corsair HX-750w, MSI GTX660 Twin Frozr
Server2012: Q9300 - 8GB DDR2 - Asus P5QL Pro - Corsair CX430 - Mirrored 2TB Seagate's with 2TB WD cav for fileshare backups, 1TB WD for OS backups

redkal13
Legit User
Legit User
Posts: 7
Joined: Wed Feb 17, 2010 2:39 pm

Re: SAPPHIRE 100270SR Radeon HD 4850 X2 in pcie2.0 16x

Post by redkal13 » Fri Feb 19, 2010 1:35 am

Ok i get it now. Thanks for your advice man.

Post Reply