I7 / 4870x2 crossfire underperforming - Benchmark update

EDIT: PCMark scores in post below.

My friend and I built him a new system this past spring. It was supposed to be a monster that would destroy anything we threw at it. Instead, we have a machine that just under performs.

Pertinent system specs

Core i7 940
EVGA E758-A1 X58
6 Gigs DDR3 1333 (Patriot)
Two Diamond Radeon 4870x2 2GB in crossfire
300 GB VelociRaptor
COOLER MASTER Silent Pro 1000W
Soundblaster X-Fi Xtreme Gamer
2560 x 1600 monitor
Win 7 RC 64 / Vista Business SP1 64

Performance testing has been by feel. No actual FPS measurements. However, we've had my system sitting next to it in the same room (which his rig should destroy) and run the same games side by side. My system is clearly running more efficiently.

My Rig:

Phenom II x4 940
DFI LP DK 790FXB-M2RSH
6 Gigs DDR2 800
Nvidia 8800 GTX
300 GB VelociRaptor
Corsair 620HX
Soundblaster Audigy
1920 x 1200 monitor
Win 7 RC 64.

Our testing has mostly been with TF2, Portal, Half-Life 2, Assassin's Creed, Left 4 Dead and Bioshock all through Steam. We attempt to run all games with max settings.

Both systems have all critical updates applied (in both OS environments for his)

We've tested every Catalyst driver from 8.7 to the 9.10 We updated his mobo BIOS at every release since we built it.

TF2 runs well, but on his system has noticeable frame hangs from time to time.

Portal is just choppy all around. Particularly on the level with the fire pit. Frame rates will drop to less than 1 in the fire room.

Half-Life 2 just doesn't run as smoothly as on my system.

Assassin's Creed, L4D and Bioshock are similar. OK performance, but less than what my AMD rig gets with the 8800 GTX. Noticeable hangs in frames from time to time like with TF2.

For L4D, some settings have to be toned down to maintain good performance. Portal runs OK with several lowered settings, except for any level with fire effects. Then it is nearly unplayable.

We've toggled Catalyst A.I., V-sync... all the usual suspects, but to no avail. The individual 4870x2s run fine individually, though we still see issues with Portal, the crossfire set-up is a worse environment. I tested one of the cards in my system and it ran perfectly. (Couldn't try crossfire due to the PSU limit)

What are we missing? Every thread I've found on the web with similar issues are under different environments, and their solutions (if they have one) haven't worked for us.

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EDIT: Had my roommate run 3DMark Vantage

This is what we got:

3DMark Score
P21655
CPU Score
18700
Graphics Score
22860

Jane Nash: 62.29 FPS
New Calico: 71.8 FPS

AI Test: 2625.14 Operations/s
Physics Test: 23.84 Operations/s

Physics test made the system crawl as we watched.

Appears that the test was done at 1280 x 1024. Didn't see how we could change it. (Trial version of 3DMark limitation?)

We're both new to benchmarking. Building and tweaking I understand, but I've never bothered with the numbers before. But this issue is over 6 months old now. Drivers, BIOS... nothing seems to improve the issue. Getting desperate.

Any ideas?

We haven't run any benchmarking software yet. The performance is way to off for numbers to even matter at this point.

As far as CF working, I know all 4 GPUs are recognized by Catalyst and are showing as linked.

Just finished the PCMark test... it looks terrible.

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PCMarkSuite
8151 PCMarks

Processor
Intel Core i7-940 (2.93GHz)
Graphics card
Diamond Viper ATI Radeon HD 4870 X2 - graphics adapter - 2 GPUs - Radeon HD 4870 X2 - 2 GB
Memory 6144 MB
Operating system Windows 7 Beta
System type 64-bit
Motherboard manufacturer EVGA
Motherboard model 132-BL-E758
Memory 6144 MB
Module 1 2047 MB
Module 2 2047 MB
Module 3 2047 MB

Processor information

Processor
Intel Core i7-940 (2.93GHz)
Physical / logical processors 1 / 8
1 / 8
Multicore 4 Processor Cores
4 Processor Cores
FSB 133 MHz
172 MHz

Display information
Graphics card
Graphics card vendor ATI Technologies
Graphics memory 1024 MB
Core clock 18 MHz
Memory clock 9 MHz
Driver name ATI Radeon HD 4870 X2
Driver version 8.661.0.0
Driver status WHQL - Not FM Approved
Linked display adapters Yes

Benchmark settings
Program Version
PCMark Vantage Revision 0 Hotfix 1
Resolution
2560x1600

Main test results

PCMarkSuite - 8151.0 PCMarks

PCMark Memories 1
CPU image manipulation
8.9 MB/s

HDD - importing pictures to Windows Photo Gallery
42.28 MB/s

PCMark Memories 2
Video transcoding - VC-1 to WMV9
5.88 MB/s

PCMark TV and Movies 1
Video transcoding - VC-1 to VC-1
1.52 MB/s

Video playback - VC-1 HD DVD with SD commentary
29.79 FPS

PCMark TV and Movies 2
HDD - Windows Media Center
60.19 MB/s

Video playback - VC-1 HD DVD with HD content
29.81 FPS

PCMark Gaming 1
Data decompression
1599.43 MB/s

GPU gaming
37.93 FPS

PCMark Gaming 2
CPU gaming
33356.54 Operations/s

HDD - gaming
15.23 MB/s

PCMark Music 1
Web page rendering - music shop
29.33 Pages/s

Audio transcoding - MP3 to WMA
1.07 MB/s

HDD - adding music to Windows Media Player
5.99 MB/s

PCMark Music 2
Audio transcoding - WAV to WMA lossless
20.18 MB/s

PCMark Communications 1
Data encryption - CNG AES CBC
5.57 MB/s

Data compression
2.04 MB/s

Windows Mail - copying
20.54 Operations/s

Sorry 2x Post, did you add the crossfire bridge?

Now that's odd...
That 3dmark score, while it does sound a bit low, is indicative of a system that should have no trouble at all playing something like portal. I honestly don't have a clue.

DO NOT run furmark. It can damage the cards.

that is so weird...... there has to be some issue with the cards? have you tried contacting the video card supplier and letting them know of the scores? this is just too weird.